Bulletin of the American Physical Society
58th Annual Meeting of the APS Division of Plasma Physics
Volume 61, Number 18
Monday–Friday, October 31–November 4 2016; San Jose, California
Session YP10: Poster Session IX (Supplemental; Postdeadline)Poster

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Room: Exhibit Hall 1 

YP10.00001: SUPPLEMENTAL 

YP10.00002: Two heretical thoughts on fusion and climate Wallace Manheimer This presents and explores 2 heretical thoughts regarding controlled fusion and climate. First, the only way that fusion can contribute to midcentury power is by switching its goal from pure fusion, to fusion breeding. Fusion breeding makes many fewer demands on the fusion device than does pure fusion. Fusion breeding could lead to a sustainable, carbon free, environmentally and economically viable, midcentury infrastructure, with little or no proliferation risk, which could provide terawatts of power for the world. The second involves climate. We are all inundated by media warnings, not only of warming from $CO_2$ in the atmosphere, but all sorts of other environmental disasters. For instance there will be more intense storms, rising sea levels, wild fires, retreating glaciers, droughts, loss of agricultural productivity… These assertions are very easy to check out. Such a search shows that we are nowhere near any sort of environmental crisis. The timing could be serendipitous; the time necessary to develop fusion breeding could well match up to the time when it is needed so as to avoid harm to the earth’s climate and/or depletion of finite energy resources. [Preview Abstract] 

YP10.00003: Lifting of the VlasovMaxwell Bracket by Lietransform Method A.J. Brizard, P.J. Morrison, J.W. Burby The VlasovMaxwell equations possess a Hamiltonian structure expressed in terms of a Hamiltonian functional and a functional bracket. The transformation (``lift'') of the VlasovMaxwell bracket [1,2] induced by the dynamical reduction of singleparticle dynamics is investigated when the reduction is carried out by Lietransform perturbation methods. The ultimate goal of this work is to derive explicit Hamiltonian formulations for the guidingcenter and gyrokinetic VlasovMaxwell equations that have important applications in our understanding of turbulent magnetized plasmas. \newline In particular, we investigate how the Hamiltonian properties of the reduced VlasovMaxwell bracket survive (1) the {\it closure} problem: the process of truncation of the guidingcenter VlasovMaxwell bracket at a finite order in $\epsilon$ (so far expressions have been derived at all orders in $\epsilon$) and (2) the {\it averaging} problem: the process by which which the gyroangle is eliminated from the guidingcenter VlasovMaxwell bracket (since guidingcenter VlasovMaxwell equations do not involve the fast gyromotion time scale). \newline [1] P.J.~Morrison, PoP 20 (2013) 012104. \newline [2] A.J.~Brizard, P.J.~Morrison, J.W.~Burby, {\it et al.}, submitted for publication. [Preview Abstract] 

YP10.00004: Lagrangian and topological invariants in extended MHD Manasvi Lingam Although extended MHD has been known since the 1950s, systematic studies of its Lagrangian invariants are rare. Here, such a study is undertaken to indicate how the generalizations of the Ertel and helicity invariants can be duly constructed, thereby extending the analysis of [1]. A general procedure for obtaining more intricate Lagrangian invariants is also delineated. The Alfven theorems, pertaining to flux conservation and magnetofluid connections, are derived for extended MHD. Some exact solutions with a nontrivial topology are presented, and connections with other fields of physics are established. In particular, the MHD topological soliton, discovered in the 1980s, is shown to possess natural counterparts in extended MHD. The consequences of these models in astrophysics and fusion are briefly discussed.\\ \noindent [1] M. Lingam, G. Miloshevich, P. J. Morrison, Phys. Lett. A, 380, 2400 (2016) [Preview Abstract] 

YP10.00005: Effect of RF Waves on Ionospheric Fluctuations S Sen, J Martinell It is demonstrated that the ponderomotive force of the rf waves can stabilize many lowfrequency modes in the ionosphere. The underlying physics of this stabilization mechanism is identified and is found to be rather general in the sense that all potential driftlike instabilities are expected to be affected in a similar way. It is also shown that this stabilization can be achieved for rather modest values of the rf power. Applications of this finding to ionospheric fluctuation will be discussed. [Preview Abstract] 

YP10.00006: Robust spherical directdrive design for NI Laurent Masse, O. Hurricane, P. Michel, R. Nora, M. Tabak Achieving ignition in a directdrive or indirectdrive cryogenic implosion is a tremendous challenge. Both approaches need to deal with physic and technologic issues. During the past years, the indirect drive effort on the National Ignition Facility (NIF) has revealed unpredicted lost of performances that force to think to more robust designs and to dig into detailed physics aspects. Encouraging results have been obtained using a strong first shock during the implosion of CH ablator ignition capsules. These ''highfoot'' implosion results in a significantly lower ablation RayleighTaylor instability growth than that of the NIC point design capsule. The tradeoff with this design is a higher fuel adiabat that limits both fuel compression and theoretical capsule yield. The purpose of designing this capsule is to recover a more ideal onedimensional implosion that is in closer agreement to simulation predictions. In the same spirit of spending energy on margin, at the coast of decreased performance, we are presenting here a study on ''robust'' spherical direct drive design for NIF. This 2Shock direct drive pulse shape results in a high adiabat (\textunderscore \textgreater 3) and low convergence (\textless 17) implosion designed to produce a near 1Dlike implosion. We take a particular attention to design a robust implosion with respect to longwavelength non uniformity seeded by power imbalance and target offset. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DEAC5207NA27344 [Preview Abstract] 

YP10.00007: Enhanced ion acceleration in the transition regime from opaque to transparent plasmas Rohini Mishra, Frederico Fiuza, Siegfried Glenzer Using ParticleinCell (PIC) simulations, we investigate ion acceleration in highintensity laserplasma interactions in for targets that become laser transparent to the laser during the interaction process. A theoretical model is developed to derive an optimal target electron areal density `n.L' as a function of laser normalized intensity and the pulse duration in the laser transparent regime. A large schematic parametric scan for a wide range of target electron density (n) and thickness (L) is performed and shown to be consistent with analytical prediction. Our simulations show that iIon acceleration in optimal conditions relies on the reheating of the expanding sheath electrons by the laser and enhancing enhancement of the Target Normal Sheath Acceleration (TNSA) electric field after the plasma becomes transparent to the laser light. This enhanced TNSA field decays slower compared to conventional TNSA resulting in significantly higher proton energies. Our results open the way to the exploration of optimized ion acceleration in the transparency regime, not only with nmscale foils but also with recently developed micronscale hydrogen jets. [Preview Abstract] 

YP10.00008: DSMC simulations of leading edge flatplate boundary layer flows at high Mach number Dr. Sahadev Pradhan The flow over a 2D leadingedge flat plate is studied at Mach number \textit{Ma }$= (U_{inf}/ \backslash $\textit{sqrt\textbraceleft k}$_{B}T_{inf}$\textit{/ m\textbraceright ) }in the range \textit{\textless Ma \textless 10}, and at Reynolds number number \textit{Re }$= (L_{T} U_{inf}$\textit{ rho}$_{inf\thinspace }$\textit{)/ mu}$_{inf\thinspace }$ equal to 10$^{\mathrm{\thinspace \thinspace }}$using twodimensional (2D) direct simulation Monte Carlo (DSMC) simulations to understand the flow phenomena of the leadingedge flat plate boundary layer at high Mach number. Here, $L_{T}$is the characteristic dimension, $U_{inf}$and $T_{inf}$are the free stream velocity and temperature, \textit{rho}$_{inf}$ is the free stream density, $m$is the molecular mass, \textit{mu}$_{inf\thinspace }$is the molecular viscosity based on the free stream temperature $T_{inf},$and $k_{B}$is the Boltzmann constant. The variation of streamwise velocity, temperature, numberdensity, and mean free path along the wall normal direction away from the plate surface is studied. The qualitative nature of the streamwise velocity at high Mach number is similar to those in the incompressible limit (parabolic profile). However, there are important differences. The amplitudes of the streamwise velocity increase as the Mach number increases and turned into a more flatter profile near the wall. There is significant velocity and temperature slip ((Pradhan and Kumaran, J. Fluid Mech2011); (Kumaran and Pradhan, J. Fluid Mech2014)) at the surface of the plate, and the slip increases as the Mach number is increased. It is interesting to note that for the highest Mach numbers considered here, the streamwise velocity at the wall exceeds the sound speed, and the flow is supersonic throughout the flow domain. [Preview Abstract] 

YP10.00009: The generalized Onsager model and DSMC simulations of highspeed rotating flows with product and waste baffles Dr. Sahadev Pradhan The generalized Onsager model for the radial boundary layer and of the generalized CarrierMaslen model for the axial boundary layer in a highspeed rotating cylinder ((S. Pradhan {\&} V. Kumaran, J. Fluid Mech., 2011, vol. 686, pp. 109159); (V. Kumaran {\&} S. Pradhan, J. Fluid Mech., 2014, vol. 753, pp. 307359)), are extended to a multiply connected domain, created by the product and waste baffles. For a single component gas, the analytical solutions are obtained for the sixthorder generalized Onsager equations for the master potential, and for the fourthorder generalized CarrierMaslen equation for the velocity potential. In both cases, the equations are linearized in the perturbation to the base flow, which is a solidbody rotation. An explicit expression for the baffle stream function is obtained using the boundary layer solutions. These solutions are compared with direct simulation Monte Carlo (DSMC) simulations and found excellent agreement between the analysis and simulations, to within 15{\%}, provided the wallslip in both the flow velocity and temperature are incorporated in the analytical solutions. [Preview Abstract] 

YP10.00010: Charged Particle Transport in HighEnergyDensity Matter Liam Stanton, Michael Murillo Transport coefficients for dense plasmas have been numerically computed using an effective Boltzmann approach. We have developed a simplified effective potential approach that yields accurate fits for all of the relevant cross sections and collision integrals. Our results have been validated with molecular dynamics simulations for selfdiffusion, interdiffusion, viscosity, thermal conductivity and stopping power. Molecular dynamics has also been used to examine the underlying assumptions of the Boltzmann approach through a categorization of behaviors of the velocity autocorrelation function in the Yukawa phase diagram. Using a velocitydependent screening model, we examine the role of dynamical screening in transport as well. Implications of these results for Coulomb logarithm approaches are discussed. [Preview Abstract] 

YP10.00011: Diffusion of external magnetic fields into the coneinshell target in the fast ignition Atsushi Sunahara, Tomoyui Johzaki, Hideo Nagatomo, Shouhei Sakata, Kazuki Matsuo, Seungho Lee, Shinsuke Fujioka, Hiroyuki Shiraga, Hiroshi Azechi We simulated the diffusion of externally applied magnetic fields into coneinshell target in the fast ignition. In this ignition scheme, the externally magnetic fields up to kiloTesla is used to guide fast electrons to the highdense imploded core, and understanding diffusion of the magnetic field is one of the key issues for increasing the coupling efficiency from the heating laser to the imploded core. In order to study the magnetic field, we have developed 2D cylindrical Maxwell equation solver with Ohm’s law, and carried out simulations of diffusion of externally applied magnetic fields into a coneinshell target. Also, we estimated the conductivity of the cone and shell target based on the assumption of Sahaionization equilibrium. We present our results of diffusion of magnetic fields. We also show that the target is heated by the eddy current. Because of the density and temperature dependence of the conductivity, the magnetic fields diffuse into the material with varying conductivity. Consequently, the magnetic fields into the coneinshell target depend on the temporal profile of the magnetic fields as well as the electrical and thermal properties of the material. [Preview Abstract] 

YP10.00012: A microstrip photonic crystal with bandgap tuning using laserproduced plasmas. Benjamin Wang, Mark Cappelli A tunable microstrip bandgap device with plasma elements is designed and experimentally characterized. A straight microstrip waveguide with patterned holes in the copper ground plane form a photonic bandgap structure, with an operating frequency of 2 GHz  12 GHz. Various configurations of the microstrip allow for bending and switching, with addition of tunable elements for active tunability. ANSYS HFSS simulations were performed to characterize the transmission characteristics of the device. A switchable plasma element is integrated into the holes in the ground plane using a pulsed laser generated plasma, allowing for active tunability of attenuation and switching of the device. The plasma element in the ground plane bandgap structure allows the transmission in the bandgap frequencies to be tuned as a function of plasma density. [Preview Abstract] 

YP10.00013: Properties of Masergenerated Alfv\'{e}n wave in a Large Laboratory Device Ziyan Zhu, Seth Dorfman, Troy Carter, George Morales, Mary Clark, Giovanni Rossi This research is motivated by the investigations of the natural Alfv\'{e}n wave maser, which refers to the resonant amplification of Alfv\'{e}n wave in the earthsurrounding plasmas. A resonant cavity that results from applying a locally nonuniform magnetic field to a plasma source region between the anode and cathode of the Large Plasma Device creates the maser. In this research, a lanthanum hexaboride (LaB6)) cathode is used as the plasma source. Above an excitation threshold, selective amplification produces a highly coherent, large amplitude Alfv\'{e}n wave that propagates out of the resonator through a semitransparent mesh anode into the plasma column where the magnetic field is uniform. The excitation threshold depends on the discharge voltage, and it increases as background magnetic field strength increases; this threshold influences the maser behaviors, including amplitude modulations. The maser with LaB6 source has m $=$ 1 mode and exhibits a righthanded rotation, which is consistent with the electron diamagnetic drift rotation, supporting the possibility of a drift Alfv\'{e}n wave maser. To distinguish between drift and shear Alfv\'{e}n waves, a new experiment with the maser cavity excited by a driving circuit was performed. This allows us to access low frequencies (compared to $\omega $*) that cannot be spontaneously driven. The dispersion relation of this driven maser is under investigation. The experimental results will motivate future Alfv\'{e}n wave study in laboratory devices and thus help better understand space plasma physics such as testing the theory of Alfv\'{e}nwaveinduced heating of stellar atmosphere. [Preview Abstract] 

YP10.00014: Ultrahigh gradient superradiant amplification in the wake of an intense laser pulse Jason Cole, Matthew Streeter, Nelson Lopes, Kristjan Poder, Jonathan Wood, Nicholas Dover, Michael Bloom, Andreas Dopp, William Schumaker, Chris Murphy, Gianluca Sarri, Matt Zepf, Alec Thomas, Karl Krushelnick, Stuart Mangles, Zulfikar Najmudin The peak intensity attainable in a highpower laser system is limited by the damage thresholds of its components, necessitating the use of large and expensive optics. Backwards Raman amplification (BRA) has been proposed as a method for the amplification of short pulses, where a pump beam resonantly scatters into a seed beam in the presence of a plasma which is not susceptible to optical damage. While promising in simulation, BRA has proven a significant experimental challenge with few standout successes. An alternative technique which operates at higher pump intensities is superradiant amplification (SRA), relaxing the requirements on frequency matching of the pump and seed which constrain experimental implementations of BRA. Here we demonstrate that at pump intensities three orders of magnitude above those conventionally used in BRA, the SRA mechanism supports the 10$^5$ fold amplification of an equalfrequency seed pulse over micron length scales. [Preview Abstract] 

YP10.00015: Experimental Validation of Plasma Metasurfaces as Tunable THz Reflectors Roberto Colon Quinones, Thomas Underwood, Mark Cappelli Measurements are presented which validate the use of plasma metasurfaces (PMs) as potential tunable THz reflectors. The PM considered here is an n x n array of laser produced plasma kernels generated by focusing the fundamental output from a 2 J/p Qswitched Nd:YAG laser through a multilens array (MLA) and into a gas of varying pressure. An M Squared FireflyTHz laser is used to generate a collimated pulse of THz light, which is then directed to the PM at varying angles of incidence. The reflected energy is measured using a GentecEO SDX1187 joulemeter probe to characterize the surface impedance or reflectivity. In this presentation, we will compare the measured reflectance to values obtained from theoretical predictions and 3D finitedifference timedomain (FDTD) simulations. [Preview Abstract] 

YP10.00016: The effects of differential flow between rational surfaces on toroidal resistive MHD modes Dylan Brennan, Michael Halfmoon, Dov Rhodes, Andrew Cole, Michio Okabayashi, Carlos PazSoldan, John Finn Differential flow between resonant surfaces can strongly affect the coupling and penetration of resonant components of resistive modes, and yet this mechanism is not yet fully understood. This study focuses on the evolution of tearing instabilities and the penetration of imposed resonant magnetic perturbations (RMPs) in tokamak configurations relevant to DIIID and ITER, including equilibrium flow shear. It has been observed on DIIID that the onset of tearing instabilities leading to disruption is often coincident with a loss of differential rotation between a higher m/n tearing surface (normally the 4/3 or 3/2) and a lower m/n tearing surface (normally the 2/1). Imposing RMPs can strongly affect this coupling and the torques between the modes. We apply the nonlinear 3D resistive magnetohydrodynamic (MHD) code NIMROD to study the mechanisms by which these couplings occur. Reduced MHD analyses are applied to study the effects of differential flow between resonant surfaces in the simulations. Interaction between resonant modes can cause significant energy transfer between them, effectively stabilizing one mode while the other grows. The flow mitigates this transfer, but also affects the individual modes. The combination of these effects determines the nonlinear outcome. [Preview Abstract] 

YP10.00017: Dimensional crossover in Rayleigh Taylor flows driven by time dependent accelerations Aklant K. Bhowmick, Snezhana Abarzhi We investigate the nature of dimensional crossover i.e. transition between the nearly isotropic 3D square bubbflows les to highly anisotropic 2D flows in Rayleigh Taylor (RT) instability. Power law time dependence of the acceleration is considered with the emphasis on subregime, where the behavior is RT type. We consider flow with rectangular symmetry and obtain the 3D square and 2D limits with leading order rectangular corrections. Solutions evolve as power law and solutions form a two parameter family parametrized by the principal curvatures of the bubble. The bubbles with “near circular contour” separate the 2dimensional solution space into two distinct regimes having distinct properties under the dimensional crossover. In one regime, the elongated bubbles transform to 2D solutions, whereas in the other the elongated bubbles flatten under a dimensional crossover. 3D square bubbles are universally stable whereas 2D bubbles are unstable with respect to 3D modulations, implying that the dimensional crossover is discontinuous. The time dependence affects the growth/decay of perturbations and has no consequence on the overall stability properties of the solution. [Preview Abstract] 

YP10.00018: Dimensional crossover in RichtmyerMeshkov unstable flows in the presence of pressure fluctuations Aklant K. Bhowmick, Snezhana Abarzhi We analyze the RichtmyerMeshkov interfacial dynamics instability in the presence pressure fluctuations. Pressure fluctuations are scale invariant and are modeled by an effective time dependent acceleration field with power law exponent 2. The group theory based analysis is applied to 3D rectangular p2mm, 3D square p4mm and 2D pm1 RM flows. From the symmetry analysis, we find that 3D square and 2D bubbles form a one parameter family and 3D rectangular bubbles form a two parameter family. The families are parametrized by the principal curvature(s). The bubble velocity and Fourier amplitude profiles exhibit RM type behavior for weak accelerations and RT type behavior for strong accelerations. Under the dimensional crossover, the bubbles elongated in one of the directions reduce to the 2D solutions, whereas the bubbles elongated in the other direction flatten. Stability analysis shows that 3D square bubbles are stable with respect to isotropic as well as anisotropic perturbations. 2D bubbles are unstable to 3D perturbations. No continuous transition is possible between 3D square and 2D bubbles and the dimensional crossover is discontinuous for both strong and weak pressure fluctuations. [Preview Abstract] 

YP10.00019: Effect of pressure fluctuations on RichtmyerMeshkov coherent structures Aklant K. Bhowmick, Snezhana Abarzhi We investigate the formation and evolution of Richtmyer Meshkov bubbles after the passage of a shock wave across a two fluid interface in the presence of pressure fluctuations. The fluids are ideal and incompressible and the pressure fluctuations are scale invariant in space and time, and are modeled by a power law time dependent acceleration field with exponent 2. Solutions indicate sensitivity to pressure fluctuations. In the linear regime, the growth of curvature and bubble velocity is linear. The growth rate is dominated by the initial velocity for weak pressure fluctuations, and by the acceleration term for strong pressure fluctuations. In the nonlinear regime, the bubble curvature is constant and the solutions form a one parameter family (parametrized by the bubble curvature). The solutions are shown to be convergent and asymptotically stable. The physical solution (stable fastest growing) is a flat bubble for small pressure fluctuations and a curved bubble for large pressure fluctuations. The velocity field (in the frame of references accounting for the background motion) involves intense motion of the fluids in a vicinity of the interface, effectively no motion of the fluids away from the interfaces, and formation of vortical structures at the interface. [Preview Abstract] 

YP10.00020: ABSTRACT WITHDRAWN 

YP10.00021: Intense, Narrowband THz Emission from a Current Source Immersed in Cutoff of Plasmalike Media Min Sup Hur, Bernhard Ersfeld, Adam Noble, Hyyong Suk, Dino Jaroszynski Recently we found an interesting behavior of the electromagnetic radiation emerging from cutoff condition of a plasmalike medium, when it is driven by a current source. Differently from conventional total reflection of the incident wave at the cutoff, we found a spatially diffusing and temporally growing electromagnetic field from the current source. Direct result of such diffusiongrowth is the selectively enhanced emission (SEE) at the cutoff frequency from a generally broadband current oscillation. We demonstrate examples demonstrating the SEE. One is the twocolordriven THz emission from field ionization of the gas slab located in a tapered waveguide. The emission propagating through the waveguide exhibits a significantly enhanced spectral density at the cutoff frequency. The other example is the THz emission from a magnetized plasma driven by two colliding ultrashort laser pulses. Since a very narrowband emission can be selectively enhanced from a broadband radiation source, the SEE concept can be used for conversion of a general broadband THz source to a narrowband one by locating it in a metastructure such as the waveguide or a plasmalike medium. We discuss other possible systems to which SEE can be applied. [Preview Abstract] 

YP10.00022: A relativistic selfconsistent model for studying enhancement of space charge limited emission due to counterstreaming ions M. C. Lin, J. Verboncoeur A maximum electron current transmitted through a planar diode gap is limited by space charge of electrons dwelling across the gap region, the so called space charge limited (SCL) emission. By introducing a counterstreaming ion flow to neutralize the electron charge density, the SCL emission can be dramatically raised, so electron current transmission gets enhanced. In this work, we have developed a relativistic selfconsistent model for studying the enhancement of maximum transmission by a counterstreaming ion current. The maximum enhancement is found when the ion effect is saturated, as shown analytically. The solutions in nonrelativistic, intermediate, and ultrarelativistic regimes are obtained and verified with 1D particleincell simulations. This selfconsistent model is general and can also serve as a comparison for verification of simulation codes, as well as extension to higher dimensions. [Preview Abstract] 

YP10.00023: Study on the After Cavity Interaction in a 140 GHz Gyrotron Using 3D CFDTD PIC Simulations M. C. Lin, S. Illy, K. Avramidis, M. Thumm, J. Jelonnek A computational study on after cavity interaction (ACI) in a 140 GHz gryotron for fusion research has been performed using a 3D conformal finitedifference timedomain (CFDTD) particleincell (PIC) method. The ACI, i.e. beam wave interaction in the nonlinear uptaper after the cavity has attracted a lot of attention and been widely investigated in recent years. In a dynamic ACI, a TE mode is excited by the electron beam at the same frequency as in the cavity, and the same mode is also interacting with the spent electron beam at a different frequency in the nonlinear uptaper after the cavity while in a static ACI, a mode interacts with the beam both at the cavity and at the uptaper, but at the same frequency. A previous study on the dynamic ACI on a 140 GHz gyrotron has concluded that more advanced numerical simulations such as particleincell (PIC) modeling should be employed to study or confirm the dynamic ACI in addition to using trajectory codes. In this work, we use a 3D full wave time domain simulation based on the CFDTD PIC method to include the rippledwall launcher of the quasioptical output coupler into the simulations which breaks the axial symmetry of the original model employing a symmetric one. A preliminary simulation result has confirmed the dynamic ACI effect in this 140 GHz gyrotron in good agreement with the former study. A realistic launcher will be included in the model for studying the dynamic ACI and compared with the homogenous one. [Preview Abstract] 

YP10.00024: The Correlation between Physical Environment and Student Engagement. Jorge CarmonaReyes, Li Wang, Lorin Matthews, Mike Cook, Truell Hyde In its second year of an educational research collaboration on the convergence between physical environment, pedagogical methods, student attainment and academic performance, CASPER along with the Region 12 Education Service Center and Huckabee Inc. have completed their initial quantitative study. This project examined the impact of the physical environment on student engagement, employing a flexibility construct and examination of teacher mobility and places of centeredness. Data analysis showed a positive correlation between student engagement and classroom flexibility for two locations having statistically significant differences in flexibility scores. The research is now being extended to examine a laboratory setting (in this case, a complex plasma lab) where the results will be used to enhance student work efficiency while also increasing safety within the lab. Details will be discussed in this presentation. [Preview Abstract] 

YP10.00025: The calculation of the effective diamagnetic frequency using BOUT$++$ code Y. M. Wang, X. Q. Xu, P. B. Snyder, T. H. Osborne The effective diamagnetic frequency of the peelingballooning modes is evaluated by the ideal MHD and the 2fliud models. This effective diamagnetic frequency is used in the EPED code to predict the pedestal width and height. In the DIIID detachment experiments, the difference of the measured pedestal height and predicted pedestal height become more significant for the higher density cases. In the higher gas puffing case, the bootstrap current is suppressed and the decrease of the pressure gradient will lead to less ion diamagnetic stabilization. A new effective diamagnetic model is needed to improve the accuracy of the pedestal parameters prediction. The effective diamagnetic frequency with different parameters is calculated by BOUT$++$ 3field linear code using dbm19 equilibrium generated by TOQ code. The equilibriums are generated using sets of different fraction of bootstrap current, elongation, q$_{\mathrm{95}}$, pedestal width and height. A new formula of effective diamagnetic frequency with these parameters is generated by fitting the simulation results. Using the new formula, the comparison between the simulation results and the experimental measurements will be conducted. [Preview Abstract] 

YP10.00026: ABSTRACT WITHDRAWN 

YP10.00027: Experimental Study of the Influence of Surface Conditions on Explosive Electron Emission From a Pin Cathode S.A. Pikuz, T.A. Shelkovenko, D.A. Hammer, E.V. Parkevich, I.N. Tilikin, A.R. Mingaleev, A.V. Agafonov Most theories of Explosive Electron Emission are based on the idea of cathode flares developing after explosion of metal whiskers on the cathode surface. The spatial structure of the flare, its origin and the process of flare development are still a matter of conjecture. In this work we used picosecond duration high resolution laser probing and Xpinch pointprojection Xray radiography to directly observe whisker explosion in a highcurrent diode. Pin cathodes made from thin 525 µm W, Cu or Mo wires were used as the load in return current circuits of hybrid Xpinches on the XP and BIN pulsers. Pin length, pinanode gap and wire surface conditions were varied over a wide range. The diode current and voltage were measured. In experiments with small wireanode gap (0.1 – 1 mm) development of the expanded dense core of the wire was observed except with lengths of 100200 microns. Strong mitigation of the electron emission was observed in experiments with heated pins. [Preview Abstract] 

YP10.00028: POSTDEADLINE 

YP10.00029: Anyon Superconductivity of Sb WH Maksoed, August Parengkuan In any permutatives to Pedro P. Kuczhynski from Peru, for anyon superconductivity sought EZ Kuchinskii,\textit{et.al}: ``\textbf{Anion height dependence of T}$_{\mathrm{\mathbf{c}}}$\textbf{ {\&} d.o.s of Febased Superconductors''}, 2010 as well as ``on the basis of electron microscopy {\&} AFM measurements, these phenomena are quantified with focus on fractal dimension, particle perimeter {\&} size of the side branch(tip width) in bert Stegemann, \textit{et.al}:\textbf{Crystallization of Sb nanoparticlesPattern Formation {\&} Fractal Growth'',}\underline {J.PhysChem B.,} 2004. For dendritic {\&} dendrimer fractal characters shown further:''antimony denrites were found to be composed of wellcrystallized nanoflakes with size 204 nm'' Bou Zhau, \textit{et.al , }\underline {MaterialLetters, }\textbf{59 }( 2005 ). The alkyl triisopropyl attached in TIPSb those includes in DNA, haemoglobin membrane/fixedbed reactor for instance quotes in Dragony Fu, \underline {Nature Review Cancer, } \textbf{12 }( Feb 2012 ). [Preview Abstract] 

YP10.00030: Allied fractal  Signal 73140 engines to HE. Mr. DrHC Jakob OETAMA'' WH Maksoed Firstly :*) Boeing 85 {\%} probability wind 4 PaxISA conditions NBAA for `highly efficient AlliedSignal 73140 engines of SpX, herewith adopts Beeckman D to Beechjet 400A usually used by HE. Mr. Prof. DrIng B.J. HABIBIE by ``per se''. For ``Fractal signals {\&} Spacetime Cartoons'' planned to be presented April 17, 2016 in SouthFoyer Room , Salt Lake City UTAH, the US ever retrieved M. Riebe, \textit{et.al}: Deterministic Quantum Teleportation with Atoms'', \underline {NPG }2004. Further, for poetic `fractal Heart' in an coincidences are ``the hardest thing in the World to understand is the income TAX'' notion from Albert Einstein to ``TinTin'' through Gilles Holst {\&} ``dimer Holstein'' as well as took a terms of reference of Liu {\&} Zhang: Adiabatic Limits {\&} Foliations'' to relates infinite Hund coupling to suji leafs of dracaena angustifolia courtesies of Willybrordus Surendra Rendra. [Preview Abstract] 

YP10.00031: Real {\&} Financial Sectors, ``koq Financenaann..'' {\&} Elbio Dagotto's Interactions WH Maksoed In conjunctions between PMRI/Pendidikan Matematika Realistik Indonesia fom Dr. RK Sembiring to ``ASTRANOMICS'': the New Reality in Business Aviation herewith provided `interaction between real {\&} financial sector' and financialisation from Heinrich Bortis: \textbf{``the Real {\&} Financial Sector of a Monetary Production Economy in the perspective of classicalKeynesian political economy'' }ever specifies ``sector Riil'' from HE. Mr. Ir. Aburizal Bakrie. Instead describes the context of CMR/Colossal Magnetoresistance cq Carlos SLIM, the richest entrepreneur in the world 2014 also obtaines Dagotto {\&} Tokura: \textbf{``Strongly correlated Electronic Materials: Present {\&} Future'', }\underline {MRS Bulletin, } Nov, 2008. Ever existed of UN Secretary General Kofie Atta Annan , for \textit{LihAT TAruh di mana?'' } are `` \textit{`koq Financenaann..?'' }inbetween conjunctions. CMR are other notions of GiantMagnetoresistance from Fert {\&} Grundberg who awarded with Nobel Prize in Physics, 2007. [Preview Abstract] 

YP10.00032: Between Lights {\&} Batteries uses of SnLi WH Maksoed Have been taught in ITB whereas according Maxwell, ``lights'' are electromagnetic waves. As well as distinguished by their ``quantum phases of electrons'' classification focuses on the motion of the charge carried by electron, a study of the spin configuration in the electron wavefunction, obtained rich variety of magnetic phases includes ferromagnets {\&} antiferromagnets. But: ``Why the lights of electromagnetic waves do not electrically causes in direct human sense?'' As if the lights as EM waves ensuing through MATTERS, he can be used to generates electric currents through batteries just like SnLi involving Libatteries. Their atomic number 503 furthers ever concludes `` a high reversible capacity is a key feature for any RECHARGEABLE battery'' Pedersen, et.al : ``The Reversible Lithiation of SnO; a threephase process'', 2015. In any communitical occurring just like `` can pay with lithium?''phrases answered with ``Ayatollah'' have been retrieved the isopropyllithium, in alkylwaitings of antimony, the Sb. [Preview Abstract] 

YP10.00033: Any ``p'' $+$ ``se'' Between GrabarKitarovic {\&} perovskite manganite25 WH Maksoed Of TTM Palstra,et.al :''Electron correlations on mesoscopic scale'' {PhysRevLet, } 1993 who meets at ``a transition metal ion in an octahedral oxygen cage forming perovskite structure''Dagotto {\&} Tokura, 2008 provides the Colossal Magnetoresistance Effect observed in Monte Carlo simulations and ferromagnetic {\&} chargeordered states in models for Manganites, realms A. Fert {\&} P. Grundberg Nobel Prize in physics 2007 GMR/GiantMagnetoresistance winning accompanies current President of Croatia: GrabarKitarovic. Furthers, a family of magnetic nanocomposites, the so called molecular cluster, there retrieves `magnetic molecular clusters like Mn12 {\&} Fe8 bridge the atomic {\&} mesoscopic scales' describes by NP Konstatinidis, et.al in ``Magnetism on a Mesoscopic Scale: Molecular Nanomagnets bridging Quantum {\&} Classical Physics'', Journal of Physics: Conference series, 303 ( 2011) ought to be related to at least singlemolecular magnets/Molecular Nanomagnets. [Preview Abstract] 

YP10.00034: NIF Discovery Science Eagle Nebula* Jave Kane, David Martinez, Marc Pound, Robert Heeter, Channing Huntington, Alexis Casner, Bruno Villette, Roberto Mancini For almost 20 years a team of astronomers, theorists and experimentalists have investigated the creation of the famous Pillars of the Eagle Nebula and similar parsecscale structures at the boundaries of HII regions in molecular hydrogen clouds, using a combination of astronomical observations, astrophysical simulations, and recently, scaled laboratory experiments. Eagle Nebula, one of the National Ignition Facility (NIF) Discovery Science programs, has completed four NIF shots to study the dense `shadowing' model of pillar formation, and been awarded more shots to study the `cometary' model. These experiments require a longduration drive, 30 ns or longer, to generate deeply nonlinear ablative hydrodynamics. A novel xray source featuring multiple UVdriven hohlraums driven is used. The source directionally illuminates a science package, mimicking a cluster of stars. The first four NIF shots generated radiographs of shadowingmodel pillars, and suggested that cometary structures can be generated. The velocity and column density profiles of the NIF shadowing and cometary pillars have been compared with observations of the Eagle Pillars made at millimeter observatories, and indicate cometary growth is key to matching observations. *Prepared by LLNL under Contract DEAC5207NA27344. [Preview Abstract] 

YP10.00035: ABSTRACT WITHDRAWN 

YP10.00036: Development of a spectroscopic technique for simultaneous magnetic field, electron density, and temperature measurements in Zpinch plasmas Eric Dutra, Radu Presura, Aaron Covington, Roberto Mancini, Timothy Darling, William Angermeier Visible spectroscopic techniques are often used in plasma experiments to measure Bfield induced Zeeman splitting, electron densities via Stark broadening, and temperatures from Doppler broadening. However, when electron densities and temperatures are sufficiently high, the broadening of the Stark and Doppler components can dominate the emission spectra and obscure the Zeeman component. In this research, we are developing a timeresolved multiaxial technique for measuring the Zeeman, Stark, and Doppler broadened line emission of dense magnetized plasmas for Zpinch. In parallel, we are developing a lineshape modeling code that incorporates the broadening effects due to Stark, Doppler, and Zeeman effects for dense magnetized plasma. Experiments were conducted at the University of Nevada (Reno) at the Nevada Terawatt Facility (NTF) using the 1 MA Zpinch (Zebra). The research explored the optical emission of Al III doublet, 4P $^{\mathrm{2}}$P$_{\mathrm{3/2\thinspace }}$to 4S $^{\mathrm{2}}$S$_{\mathrm{1/2}}$ and 4P $^{\mathrm{2}}$P$_{\mathrm{1/2\thinspace }}$to 4s $^{\mathrm{2}}$S$_{\mathrm{1/2\thinspace }}$transitions and used it to measure Zeeman, Stark, and Doppler broadened emission. The initial parameters for the line shape code are varied to simulate emission spectra. The simulated spectra are compared to experimental results. These results are used to infer temperature, electron density, and Bfields in the magnetized plasma. [Preview Abstract] 

YP10.00037: A design of the MHD stable axisymmetric mirror. Isao Katanuma It has been 35 years since the GAMMA10 tandem mirror was built. So recently PRC group is planning the construction of next linear device to perform the divertor experiment by using its endloss flux. One candidate device is considered to be a single axisymmetric mirror. The reasons are that the axisymmetric mirror has attractive features on a collaboration with the mirror community and a future mirror fusion device as well as the construction costs of pancake coils are lower than the baseball coils. The axisymmetric mirror stabilizes the interchange modes with the help of large ion endloss flux just like gas dynamic trap (GDT) and sloshing ions (its peak is located at the magnetic field line good curvature) by using the heating system. Here the large endloss flux is needed to perform the divertor experiment. The axisymmetric mirror is also planning to make use of the azimuthal plasma flow shear to suppress the interchange instabilities. This flow shear is realized by making the radial electric field, which is similar to the vortex confinement of recent GDT[1]. [1] A.Beklemishev, et.al., Fusion Sci. Tech. 57, 351 (2010). [Preview Abstract] 

YP10.00038: Electron acceleration and high harmonic generation by relativistic surface plasmons Giada Cantono Intense, short laser pulses with ultrahigh contrast allow resonant surface plasmons (SPs) excitation on solid wavelengthscale grating targets, opening the way to the extension of Plasmonics in the relativistic regime and the manipulation of intense electromagnetic fields to develop new short, energetic, lasersynchronized radiation sources. Recent theoretical and experimental studies have explored the role of SP excitation in increasing the lasertarget coupling and enhancing ion acceleration, highorder harmonic generation and surface electron acceleration. Here we present our results on SP driven electron acceleration from grating targets at ultrahigh laser intensities ($I=5\times10^{19}$W/cm$^2$, $\tau=25$fs) [Fedeli et al., PRL 116, 5001 (2016)]. When the resonant condition for SP excitation is fulfilled, electrons are emitted in a narrow cone along the target surface, with a total charge of about 100 pC and energy spectra peaked around 5 MeV. Distinguishing features of the resonant process were investigated by varying the incidence angle, grating type and with the support of 3D PIC simulations, which closely reproduced the experimental data. Open challenges and further measurements on highorder harmonic generation in presence of a relativistic SP will also be discussed. [Preview Abstract] 

YP10.00039: Ionization competition effects on population distribution and radiative opacity of mixture plasmas. Jiaolong Zeng, Cheng Gao, Jianmin Yuan The physical effects on the charge state distribution and radiative properties of mixture plasmas are investigated using a detailedlevelaccounting approximation. Detailed results are given for SiO2 plasmas. Ionization competition arising from the electronic shell structures of various atomic species in the mixture plasmas was investigated to show its effects on the charge state population distribution and spectrally resolved and Planck and Rosseland mean radiative opacities of mixture plasmas. A set of coupled equations for ionization equilibria that include all components of the mixture plasmas are solved to determine the population distributions. For a given plasma density, competition effects are found at three distinct temperature ranges, corresponding to the ionization of M, L, and Kshell electrons of Si. Taking the effects into account, the spectrally resolved and Planck and Rosseland mean opacities are systematically investigated over a wide range of plasma densities and temperatures. For a given mass density, the Rosseland mean decreases monotonically with plasma temperature, whereas Planck mean does not. Although the overall trend is a decrease, the Planck mean increases over a finite intermediate temperature regime. [Preview Abstract] 

YP10.00040: Radiative transfer of ultraintense xray pulses Cheng Gao, Jiaolong Zeng, Jianmin Yuan Radiative transfer of ultraintense xray pulses is investigated by solving a onedimensional radiative transfer equation. The populations of quantum states are obtained by solving a timedependent rate equation based on collisionalradiative approximation, which are used to determine the absorption and emission coefficients. As an illustrative example. The transmission of ultraintense xray pulses through a 1 um thick soliddensity aluminium sample is calculated and compared with a recent experiment, where good agreement is found and saturable absorption is evidently observed. [Preview Abstract] 

YP10.00041: Mathematical Foundations for Fields of Toroidal Current Loops Stephen Sharma Motivating the functions that define electromagnetic fields for a toroidal shaped current loop are centered around three main isomorphisms: fundamental additions to solutions of differential equations, solving for the geodesics of thermonuclear magnetic reactors, and constructing accurate computational combinatoric models for fusion plasmas. Thermonuclear plasmas in tokamaks are essentially loops of current where the ions and electrons create two current densities which contribute to the magnetic field of the electricity generating current loop. The toroidal shaped current loop necessitates, however, new calculus. In the Biot Savart circular loop, off axis solutions are generated from an integral of a line segment. The non circular shape's differing eccentricity is in corner regions and the linear section and requires new integration and coordinates. The solution of the incremental loop elements in the toroidal shaped coil case are now loops considered parts of semicircles and step functions. When constructing a field, new elliptic functions are going to be generated and a new polynomial functioncalled an elliptic function of the first and second kindmust be uncovered. [Preview Abstract] 

YP10.00042: Molecular Dynamics Simulation of ElectronIon Temperature Relaxation in Dense Hydrogen: Electronic Quantum Effects. Qian Ma, Jiayu Dai, Zengxiu Zhao The electronion temperature relaxation is an important nonequilibrium process in the generation of dense plasmas, particularly in Inertial Confinement Fusion. Classical molecular dynamics considers electrons as point charges, ignoring important quantum processes. We use an Electron Force Field (EFF) method to study the temperature relaxation processes, considering the nuclei as semiclassical point charges and assume electrons as Gaussian wave packets which includes the influences of the size and the radial motion of electrons. At the same time, a Pauli potential is used to describe the electronic exchange effect. At this stage, quantum effects such as exchange, tunneling can be included in this model. We compare the results from EFF and classical molecular dynamics, and find that the relaxation time is much longer with including quantum effects, which can be explained directly by the deference of collision cross sections between quantum particles and classical particles. Further, the final thermal temperature of electron and ion is different compared with classical results that the electron quantum effects cannot be neglected.. [Preview Abstract] 

YP10.00043: LaserPlasma Modeling Using PERSEUS ExtendedMHD Simulation Code for HED Plasmas Nathaniel Hamlin, Charles Seyler We discuss the use of the PERSEUS extendedMHD simulation code for highenergydensity (HED) plasmas in modeling laserplasma interactions in relativistic and nonrelativistic regimes. By formulating the fluid equations as a relaxation system in which the current is semiimplicitly timeadvanced using the Generalized Ohm's Law, PERSEUS enables modeling of twofluid phenomena in dense plasmas without the need to resolve the smallest electron length and time scales. For relativistic and nonrelativistic lasertarget interactions, we have validated a cycleaveraged absorption (CAA) laser driver model against the direct approach of driving the electromagnetic fields. The CAA model refers to driving the radiation energy and flux rather than the fields, and using hyperbolic radiative transport, coupled to the plasma equations via energy source terms, to model absorption and propagation of the radiation. CAA has the advantage of not requiring adequate grid resolution of each laser wavelength, so that the system can span many wavelengths without requiring prohibitive CPU time. For several lasertarget problems, we compare existing MHD results to extendedMHD results generated using PERSEUS with the CAA model, and examine effects arising from Hall physics. [Preview Abstract] 

YP10.00044: Communication of Information with Subparticles (Substrings) from Fifth Dimension of the Universe (Information) as the ``Fundamental Symmetry'' in the Nature. Hassan Gholibeigian, Ghasem Gholibeigian, Abdolazim Amirshahkarami, Kazem Gholibeigian Fundamental particles (strings) getting processed information from their four animated subparticles (substrings) for their motion [Gholibeigian, APS, 2015, abstract {\#}L1.027]. It seems that the source of information which particles and dark mater/energy are floating in it and whispering to its communication for getting order may be ``fifth dimension'' of the nature in addition of spacetime dimensions. In other words, spacetime can be the universe's hardware and information's dimension can be dynamic software of the universe which has always become up to date. Communication of information which has a vital role in creation and evolution of the universe, may be as the ``fundamental symmetry'' in the nature, which sparked to B.B. (Convection Bang). Communication of information leads other symmetries and supersymmetry as well as other phenomena in Universe. Before Planck time, from $0\to 10^{44}$ second, and its correspondence space needed communication of information for preparing the B.B. So, this fifth dimension has appeared for leading the processes before and after Planck time. [Preview Abstract] 

YP10.00045: Generation of intense magnetic field in a counterstreaming system Yan Yin Intense magnetic field generation by excitation of Weibel instability in dense plasmas has been investigated using particleincell (PIC) simulations. As energetic electrons driven by laser propagate in dense plasmas, a return current is excited to compensate the charge neutrality offset. In such a counterstreaming system, Weibel instability is driven, leading to current filamentation and magnetic field generation. The current filaments selforganize in coaxial structures where the relativistic current in the center is surrounded by the return current sheath and intense magnetic field. The magnetic field peaks in the current center with magnitude as high as several hundreds of MegaGauss, and decreases to zero outside the relativistic current. The influences of counterstreaming density and energy on the magnetic field generation are examined. [Preview Abstract] 

YP10.00046: PlasmaFilled RodPinch Diode for HEDLP Research Andrew Richardson, Bruce Weber, Stephen Swanekamp, Joseph Schumer, Nino Pereira, John Seely, David Mosher This poster describes recent progress on research into using the plasmafilled rodpinch (PFRP) at the Naval Research Laboratory (NRL) for warm dense matter (WDM) studies. The objective of this project is to utilize the PFRP diode and associated diagnostics to experimentally quantify the pressure, temperature, and ionization state via independent measurements in WDM comprised of ionized highZ materials (tungsten). Previous experiments and preliminary results show that the parameters of the PFRP plasma are approximately $Z = 17$, ${\rho_m} = 0.7$ g/cm${^3}$, $T = 30$ eV, $P = 16$ Mb, and ${\Gamma} = 35$. The experiments and simulations currently underway will allow for more accurate determination of these parameters, which will contribute to an enhanced understanding of these highZ materials in a WDM state. To achieve this objective, new diagnostics are being developed and current diagnostics are being refined, experiments are being performed, and numerical modeling is being carried out. This project will refine a new technique for producing WDM that can be replicated on pulsed power generators at several US universities and government laboratories, provide data for benchmarking numerical analysis codes, and develop diagnostics that should prove useful on many other WDM sources. [Preview Abstract] 

YP10.00047: Quantum simulation of structure, transport properties, and melting in dense hydrogen Dongdong Kang, Jiayu Dai, Jianmin Yuan Due to the low mass, hydrogen exhibits significant nuclear quantum effects (NQEs), especially under low temperatures and high pressures. NQEs on structure and transport properties of dense liquid hydrogen under extreme conditions are investigated using the improved centroid path integral molecular dynamics (PIMD) simulations. The results show that with the inclusion of NQEs, the radial distribution functions are obviously broadened. The selfdiffusion is largely higher while the shear viscosity is notably lower than the results of without the inclusion of NQEs due to the lower collision cross sections even when the NQEs have little effects on the static structures. The electrical conductivity is also significantly affected by NQEs. Quantum nuclear character induces complex behaviors for ionic transport properties of dense liquid hydrogen. In addition, the melting temperature of dense hydrogen is also investigated using the twophase approach based on the PIMD with the Yukawa potential describing the interaction between ions. The results show that the NQEs have a significant impact on the melting of dense hydrogen, which largely lower the melting temperature by \textasciitilde 10{\%} at the density range of 101000 g/cm$^{\mathrm{3}}$. [Preview Abstract] 

YP10.00048: Electrical Properties for Capacitively Coupled Radio Frequency Discharges of Helium and Neon at Low Pressure Murat Tanisli, Neslihan Sahin, Suleyman Demir In this study, the symmetric radio frequency (RF) electrode discharge is formed between the two electrodes placing symmetric parallel. The electrical properties of symmetric capacitive RF discharge of pure neon and pure helium have been obtained from current and voltage waveforms. Calculations are done according to the homogeneous discharge model of capacitively coupled radio frequency (CCRF) using with the data in detail. Electrical properties of bulk plasma and sheath capacitance are also investigated at low pressure with this model. This study compares the electrical characteristics and sheath capacitance changes with RF power and pressure for helium and neon discharges. Also, the aim of the study is to see the differences between helium and neon discharges' current and voltage values. Their rootmeansquare voltages and currents are obtained from Tektronix 3052C oscilloscope. Modified homogeneous discharge model of CCRF is used for low pressure discharges and the calculations are done using experimental results. It is seen that homogeneous discharge model of CCRF is usable with modification and then helium and neon discharge's electrical properties are investigated and presented with a comparison. Helium discharge's voltage and current characteristic have smaller values than neon's. It may be said that neon discharge is a better conductor than helium discharge. It is seen that the sheath capacitance is inversely correlation with sheath resistance. [Preview Abstract] 

YP10.00049: Overview of the NRL DPF program: Experiment and Modeling A. S. Richardson, S. L. Jackson, J. R. Angus, J. L. Giuliani, S. B. Swanekamp, J. W. Schumer, D. Mosher Charged particle acceleration in imploding plasmas is an important phenomenon which occurs in various natural and laboratory plasmas. A new research project at the Naval Research Laboratory (NRL) has been started to investigate this phenomenon both experimentallyin a dense plasma focus (DPF) deviceand theoretically using analytical and computational modeling. The DPF will be driven by the highinductance (607 nH) Hawk pulsedpower generator, with a rise time of 1.2 $\mu$s and a peak current of 665 kA. In this poster we present an overview of the research project, and some preliminary results from fluid simulations of the m = 0 instability in an idealized DPF pinch. [Preview Abstract] 

YP10.00050: Langmuir Probe Measurements of Capacitive Radio Frequency Discharge for Mixture Gases Murat Tanisli, Neslihan Sahin, Suleyman Demir Radio frequency discharges at low pressure have been used for very much applications, but their properties have not wellknown for plasma diagnostics. In this study, mixture discharges are obtained at the quartz glass reactor for different powers and flow rates under the laboratory conditions, and then the optical properties of gas discharges are examined by means of Langmuir probe. When the flow rates of gases and power values are changed, it can be investigated that how the plasma parameters change. Debye length is one of the important plasma parameters. Thus, the relationship between the mixture amount of two different gases and Debye length is determined from Langmuir probe data. The graphs obtained by using these data will give information about generating the discharge of mixture gases, in detail. Therefore, the results may be the useful reference for future works of industrial applications. [Preview Abstract] 

YP10.00051: Floating of Black Holes in Dimension of Information Hassan Gholibeigian, Ghasem Gholibeigian, Kazem Gholibeigian In our vision, there is dimension of information in addition of spacetime's dimensions as the fifth dimension of the universe. All of the spacetime, mater, and dark mater/energy are always floating in this dimension and whispering to its communication as well as black holes. Communication of information (CI) is done with each fundamental particle (string) from fifth dimension via its four animated subparticles (substrings) for transferring a package of complete information of its quantum state in a Planck time. Fundamental particle after process of information by its subparticles goes to its next stage while carries the stored processed information. CI as the ``fundamental symmetry'' leads all processes of the black holes as well as other phenomena. Every point of spacetime needs on time to its new package, because duration of each processing is a Planck time. So, stored soft supertranslation hairs in terms of soft gravitons or photons on black hole's horizon, or stored information on a holographic plate at the future boundary of the horizon [Hawking et. al.] can be only accessible for particles which are in those positions (horizon and its boundary), not for other locations of black hole for their fast processing. [Preview Abstract] 

YP10.00052: Wave interference in RichtmyerMeshkov flows Robert Stellingwerf, Arun Pandian, Snezhana I. Abarzhi While it is a conventional wisdom that the initial conditions determine the linear and nonlinear dynamics of the RichtmyerMeshkov (RM) flows, the research in this area is focused primarily on the effects of the wavelength and amplitude of the interface perturbation. The information is hitherto largely ignored about the influences on the evolution of RichtmyerMeshkov instability (RMI) of the relative phase of a multiwave perturbation and the interference of the perturbation waves. In this work we report a detailed study of confluence of effects of the relative phase as well as amplitudes of the interfacial waves on the structure of bubbles and spikes that is formed at the RM unstable interface after the shock passage. We show that the phase and the wave interference are important factors of the dynamics, because they influence the RM flow qualitatively and quantitatively, inclduing the symmetry of the interface, the morphology of spikes and bubbles, and the RMI growth. [Preview Abstract] 

YP10.00053: PHELIX Crenulation1 at pRad Experiment Christopher Rousculp The first PHELIX driven Crenulation experiment was fielded at the LANL LANSCE proton radiography (pRad) facility in Dec 2015. This was the first time a thinwalled tin cylinder with singlemode perturbations was shocked to meltonrelease (P \textgreater 35 kbar) in converging geometry. The perturbation inversion and growth due to the RichtmyerMeshkov Instability (RMI) is diagnosed in a 21 image pRad movie. The motivation, design, preliminary data and calculations will be discussed. [Preview Abstract] 

YP10.00054: Decomposition of Chemical Chain Molecules with Atmospheric Pressure Plasma Murat Tansli, Erol Tasal Chemical chain molecules' decomposition is an interesting subject area for the atmospheric pressure plasma applications. The effects of the atmospheric pressure argon plasma on 4((2methoxyphenyl)Diazenyl)Benzene1,3,Diol molecule at room temperature are investigated. This molecule is one of the industrial dye molecules used widely. When considering the ecological life, this molecule will be very harmful and danger. We suggest a different, easy and useful decomposing method for such molecules. Atmospheric pressure plasma jet was principally treated for this decomposing of the molecule. Fourier transform infrared spectrometry (FTIR) was used to characterization of the molecule after the plasma application to molecule in liquid phase with ethanol and methanol solvents. The atmosphericpressure plasma jet of argon (Ar) as nonequilibrium has been formed by acpower generator with frequency  24 kHz and voltage  12 kV. Characterizations for solutions prepared with ethanol and methanol solvents of molecule have been examined after applying (\textit{duration:} 3 minutes) the atmospheric pressure plasma jet. The molecule was broken at 6C7N$=$8N9C stretching peak after the plasma treatment. The new plasma photoproducts for ethanol and methanol solutions were produced as 6C7N8N$=$9C (strong, varying) and 12C$=$17O (strong, wide) stretching peaks. [Preview Abstract] 

YP10.00055: Liquidvapor equilibriumstates and critical properties of aluminum from dense plasma equationofstate Mofreh Zaghloul We present successful estimates of the critical properties and liquidvapor equilibrium states of pure aluminum fluid as predicted from a chemical model for the equationofstate of hot dense partially ionized plasma. The essential features of stronglycoupled plasma of metal vapors, such as, multiple ionization, Coulomb interactions among charged particles, partial degeneracy, and intensive short range hard core repulsion are taken into consideration. Internal partition functions of neutral, excited, and ionized species are thoughtfully evaluated in a statisticalmechanically consistent way implementing recent developments in the literature. Results predicted from the present model are discussed and carefully examined against available data and predictions in the literature. [Preview Abstract] 

YP10.00056: Simulation of Dust Generation by Injecting a Pulsed Laser to a tungsten target in DiPS2 Linear device InSun Park, InJe Kang, SungYong Shim, MinKeun Bae, HyeTeak Oh, ChaHwan Oh, KyuSun Chung A transient heat flux $\sim 50MJ/m^{2}s^{\frac{1}{2}}$ , which are frequently generated such as edge localize modes (ELMs), results in a higher thermal damage to plasma facing components (PFCs) since it is over the damage threshold $\sim 10MW/m^{2}$ of tungsten walls in a steady state at a divertor of International Thermonuclear Experimental Reactor (ITER). For studies on the mechanism of dust generation and the effect of dusts on plasmas, an experimental simulation of dust generation in Divertor Plasma Simulator  2 (DiPS2) was conducted by using an Nd:YAG pulsed laser (Energy, pulse duration, frequency) with various conditions such as a pulsed laser power, roughness of tungsten surfaces and irradiation angles. To investigate simulation results, size and quantity of dusts and its effect on plasmas were analysed by Scanning Electron Microscopy (SEM), optical diagnostics of Rayleigh scattering and electric probes (single and Mach probes). [Preview Abstract] 

YP10.00057: Interplay between turbulence, neoclassical and zonal flows during the LH transition at ASDEX Upgrade M. Cavedon, T. P\"utterich, E. Viezzer, G. Birkenmeier, T. Happel, P. Manz, F. Ryter, U. Stroth It is widely accepted that the $E \times B$ velocity shear is responsible for the suppression of the edge turbulence, thus leading to the transition from L to Hmode. However, the origin and the evolution of the edge radial electric field ($E_r$) profile and the accompanying $E \times B$ flow is still debated. The $E \times B$ flow may be generated by turbulence stresses or by collisional (neoclassical) processes via the main ion pressure gradient. A recent upgrade of the charge exchange recombination spectroscopy diagnostic at ASDEX Upgrade provides a full reconstruction of the impurity density, temperature and $E_r$ profiles at 100$\,\mu$s time resolution and allows the evaluation of the fast dynamics of these quantities during the LH transition. The behaviour of $E_r$ and the ion profiles during the LH transition will be presented for discharges with different LH power thresholds obtained via different electron densities, a $B_t$scan and a change of isotope (deuterium and hydrogen). A comparison of neoclassical and of measured $E_r$ profiles to the evolution of the turbulent fluctuation points to a leading role of neoclassical flow in the LH transition. [Preview Abstract] 

YP10.00058: Resonant laser plasma channel undulator Bifeng Lei, Jingwei Wang, Vasily Kharin, Sergey Rykovanov Laserplasma based undulators/wigglers attract a lot of attention because of their potential for the next generation of compact (\textasciitilde cm scales) radiation sources. The undulator wavelength of plasmabased devices can theoretically reach \textasciitilde 1mm or less while keeping the undulator strength on the order of unity  values so far unachievable by conventional magnetic undulators. Recently, a novel type of the plasma channel undulator/wiggler (PIGGLER) based on the wakefields generated in a parabolic plasma channel by a laser pulse undergoing centroid oscillations was proposed [PRL. , 145003 (2015)]. It was demonstrated analytically and with the help of numerical simulations that narrowbandwidth, flexible polarization and bright UVsoft Xray source can be obtained for the case when the laser pulse centroid oscillation frequency, proportional to the Rayleigh length of the laser pulse, is tuned to be much larger than the betatron frequency. In the current contribution, the case of the resonance, when the laser pulse centroid oscillation frequency is equal to the betatron frequency is discussed. It is shown that significant photon yield enhancement can be. Both linear and nonlinear regimes are studied. [Preview Abstract] 

YP10.00059: Two Dimensional Synthetic Electron Cyclotron Emission Imaging Lei Shi, Ernest J. Valeo, Benjamin J. Tobias, Gerrit J. Kramer, Chang Liu, William M. Tang Electron Cyclotron Emission (ECE) has been widely used as a measurement of the electron temperature profile in magnetically confined plasmas. The ECE Imaging (ECEI) system provides additional vertical resolutions, and is used to measure the electron temperature fluctuations. The vertical resolution is typically a few centimeters which is sometimes comparable to the vertical wave length of the underlying fluctuations. The raytracing technique used in most synthetic ECE codes to determine the origin and spatial extent of the ECE radiations is not accurate when the refraction and diffraction due to the fluctuations are important. In this presentation, we introduce a new synthetic ECEI code which solves the wave propagation up to the 2nd order of the WKB approximation, and provides full 2D information of the ECE source. We'll show that when the ECE frequency is near the cutoff, the refraction due to the fluctuations is important. A "trapping" of the ECE source by the density fluctuations is identified, and is potentially useful for determining the cross phase between electron temperature and density fluctuations. The new formalism is also used to study the Runaway Electrons contribution to the ECE signal, and provides insights to the measured ECE spectrum on DIIID. [Preview Abstract] 

YP10.00060: First Experimental Comparisons of LaserPlasma Interactions between Spherical and Cylindrical Hohlraums at the SGIII Laser Facility Ke Lan We report the first experimental comparisons of laserplasma interactions (LPI) between the spherical hohlraums and the cylindrical hohlraums at SGIII laser facility. The sphere is 1.8 mm in radius, and the cylinder is 1.2 mm in radius and 4.3 mm in length. Three kinds of fillings are considered for the hohlraums: vacuum, gasfilling without or with a capsule inside. A flattop laser pulse of up to 92.73 kJ energy with 3 ns duration is used. As observed, the LPI level of the laser beams inside the gasfilled spherical hohlraums, with or without capsule, is very close to that of the outer laser beams inside the cylindrical hohlraums with the same filling while much lower than that of inner beams. These results provide important experimental references for the choice between the octahedral spherical hohlraum and the cylindrical hohlraum of an ignition target design, which decides quite different configuration of an ignition facility. Our 2D simulations with postprocess calculations have evident differences from the data, and it indicates that the development of a 3D radiation hydrodynamic code, with more accurate physics models, is mandatory for spherical hohlraum study. [Preview Abstract] 

YP10.00061: Effect of noise on RayleighTaylor mixing with spacedependent acceleration Arun Pandian, Snezhana Abarzhi We analyze, for the first time by our knowledge, the effect of noise on RayleighTaylor (RT) mixing with spacedependent acceleration by applying the stochastic model. In these conditions, the RT mixing is a statistically unsteady process where the means values of the flow quantities vary in space and time, and there are also the space and time dependent fluctuations around these mean values. The stochastic model is derived from the momentum model and is represented by a set of nonlinear differential equations with multiplicative noise. The models equations are solved theoretically and numerically. Investigating a broad range of values of acceleration, selfsimilar asymptotic solutions are found in the mixing regime. There are two types of mixing subregimes (accelerationdriven and dissipationdriven respectively), each of which has its own types of solutions and characteristic values with the latter saturating to a value on the order of one. It is also observed that the representation of the dynamics in an implicit form is noisier as compared to the case of an explicit timedependent form. [Preview Abstract] 

YP10.00062: Effect of noise on RayleighTaylor mixing with timedependent acceleration Nora C. Swisher, Arun Pandian, Snezhana I. Abarzhi We perform a detailed stochastic study of RayleighTaylor (RT) mixing with timedependent acceleration. A set of nonlinear stochastic differential equations with multiplicative noise is derived on the basis of momentum model and group theory analysis. A broad range of parameters is investigated, and selfsimilar asymptotic solutions are found. The existence is shown of two subregimes of RT mixing dynamics – the accelerationdriven and the dissipationdriven mixing. In each subregime, statistic properties of the solutions are investigated, and dynamic invariants are found. Transition between the regimes are studied. [Preview Abstract] 

YP10.00063: Growthrate of RichtmyerMeshkov instability for small and large amplitude initial perturbation Nora C. Swisher, Arun Pandian, Zachary Dell, Robert Stellingwerf, Snezhana I. Abarzhi We study the effect of the amplitude of the initial perturbation on RichtmyerMeshkov instability (RMI) by means of Smooth Particle Hydrodynamics simulations and by the rigorous theory and the newly developed empirical model. A broad parameter regime is analyzed. Initially, the interface has a singlemode sinusoidal perturbation with the amplitude varying from 0% to 100% of its wavelength. An empirical model is developed to describe the nonmonotone dependence of the RMI growthrate on the initial amplitude. The initial growth rate of the interface has a peak value. The position of the peak depends only weakly on the Mach and Atwood numbers, whereas the peak value depends strongly on Atwood number and weakly on Mach number. The ratio of initial growth rate to background velocity is related to the energy partitioning between the interface and the bulk. We find an upper bound of the ratio of the interfacial energy to the bulk energy, and identified its scaling with the Atwood number. This peak value of the energy ratio indicates that RM interfacial growth can be controlled by initial conditions. [Preview Abstract] 

YP10.00064: Millimeter wave Diagnostic Capability on TCV Laurie Porte, Stefano Alberti, stefano coda, Basil Duval, matteo fontana, timothy goodman, Pedro MolinaCabrera TCV has a large set of millimetre wave diagnostics. Two 24 channel ECE heterodyne radiometers have been installed. Each has a line of sight perpendicular to the toroidal magnetic field. One radiometer views from the highfield side (HFS) while the second views from the lowfieldside (LFS). Each device has two mixers and local oscillators and their associated IF instrumentation and video detection. In addition, a six channel correlation ECE (CECE) radiometer has been installed for measuring electron temperature fluctuations. The CECE radiometer has a high gain antenna that can be rotated in both the toroidal and poloidal planes. All of the radiometers can be attached to a vertical line of sight allowing measurement of ECE signals generated by suprathermal electrons. A millimetrewave transmission diagnostic is being commissioned for the measurement of the absorption of the ECRH power. A 300 GHz interferometer has been installed. It is optimised for use at density below 4x10$^{\mathrm{19}}$ m$^{\mathrm{3}}$. Finally, a short pulse reflectometer is being installed and Doppler backscattering measurements have been made. All of these diagnostic systems will be described and their potential use will be detailed. [Preview Abstract] 

YP10.00065: Ionic structures and transport properties of hot dense W and U plasmas Yong Hou, Jianmin Yuan We have combined the averageatom model with the hypernetted chain approximation (AAHNC) to describe the electronic and ionic structure of uranium and tungsten in the hot dense matter regime. When the electronic structure is described within the averageatom model, the effects of others ions on the electronic structure are considered by the correlation functions. And the ionic structure is calculated though using the hypernetted chain (HNC) approximation. The ionion pair potential is calculated using the modified GordonKim model based on the electronic density distribution in the temperaturedepended density functional theory. And electronic and ionic structures are determined selfconsistently. On the basis of the ionion pair potential, we perform the classical (CMD) and Langevin (LMD) molecular dynamics to simulate the ionic transport properties, such as ionic selfdiffusion and shear viscosity coefficients, through the ionic velocity correlation functions. Due that the free electrons become more and more with increasing the plasma temperature, the influence of the electronion collisions on the transport properties become more and more important. [Preview Abstract] 

YP10.00066: Equilibrium and Instability near the Separatrix in Tokamaks Deng Zhou A local equilibrium model near the separatrix with updown symmetric double nulls is developed in this work. Shaping features like elongation, triangularity and Shafranov shift of the reference magnetic surface are taken into account in the model. The poloidal magnetic field is determined as done in Ref. [1]. The model can be used to study the effect of separatrix on the localized plasma modes such as peelingballooning modes near the tokamak edge region. As the first application we use it to calculate the Mercier index determining interchange modes. [1] Weihong Yu, Deng Zhou, and Nong Xiang, A novel local equilibrium model for shaped tokamak plasmas, Phys. Plasmas 19, 072520 ( 2012) [2] R. L. Miller, M. S. Chu, J. M. Greene, Y. R. Linliu, and R. E. Waltz, Phys. Plasmas 5, 973 (1998). [Preview Abstract] 

YP10.00067: First experimental demonstration of magneticfield assisted fast heating of a dense plasma core Shinsuke Fujioka, Shohei Sakata, Seung Ho Lee, Kazuki Matsuo, Hiroshi Sawada, Yuki Iwasa, King Fai Farley Law, Hitoki Morita, Sadaoki Kojima, Yuki Abe, Akira Yao, Masayasu Hata, Tomoyuki Johzaki, Atsushi Sunahara, Tetsuo Ozaki, Hitoshi Sakagami, Alessio Morace, Yasunobu Arikawa, Akifumi Yogo, Hiroaki Nishimura, Mitsuo Nakai, Hiroyuki Shiraga, Yasuhiko Sentoku, Hideo Nagatomo, Hiroshi Azechi Fast heating of a dense plasma core by an energetic electron beam is being studied on GEKKOLFEX laser facility. Here, we introduce a laserdriven kilotesla external magnetic field to guide the diverging electron beam to the dense plasma core. This involve placing a spherical target in the magnetic field, compressing it with the GEKKOXII laser beams and then using the LFEX laser beams injected into the dense plasma to generate the electron beam which do the fast heating. CuKa emission is used to visualize transport or heating processes of a dense plasma. Xray spectrum from a highly ionized Cu ions indicates several keV of the temperature increment induced by the LFEX. [Preview Abstract] 

YP10.00068: Demonstration of counter beam fast heating scheme by using a spherical CD shell target Y. Mori, Y. Nishimura, R. Hanayama, S. Nakayama, K. Ishii, Y. Kitagawa, T. Sekine, Y. Takeuchi, T. Kurita, Y. Kato, N. Sato, N. Kurita, T. Kawashima, T. Hioki, T. Motohiro, A. Sunahara, Y. Sentoku, E. Miura, A. Iwamoto, H. Sakagami We report fast heating of a shockimploded core under counter beam configuration that published in recent [Y. MORI et al., Phys. Rev. Lett. 117, 055001 (2016)]. Experiments are performed by using a repetitive IFE driver HAMA [Y. MORI et al., Nucl. Fusion 53, 073011 (2013)]. Experiments results show that (i) a shockimploded core with 70 micron diameter, originally deuterated polystyrene (CD) spherical shell of 500 micron diameter, is flashed by counter irradiating 110 fs, 7 TW laser pulses. The coupling efficiency from the laser to the core emission was inferred 13{\%}. A collisional ParticleInCell simulation code PICLS2D indicates a possibility that counter hot electron currents generate magnetic filaments in the imploded core. (ii) Fast electrons with energy bellow a few MeV might be trapped by these filaments in the core region supposed to be contributing to the observed Xray flash and the high coupling efficiency. These results indicate a possibility that counter irradiating fast heating scheme can improve the energy coupling into the core by hot electrons those are limited to less 10{\%} for oneside irradiation fast heating conducted so far. [Preview Abstract] 

YP10.00069: Recent upgrades to MST'’s softxray spectroscopy diagnostic M. D. Pandya, A. C. Scherer, J. Clark, A. M. DuBois, A. F. Almagri, B. E. Chapman In MST RFP plasmas, electron energization during tearing mode reconnection events was recently observed via softxray (sxr) emission [1]. Xray measurements from 325 keV during these shortlived ($<$ 100 $\mu$s) events were achieved with a detector consisting of an avalanche photodiode and a 20 ns Gaussian shaping amplifier (GSA) whose output was digitized at 500 MHz [2]. A radially resolved measurement of xray emission from 210 keV can also be made with an existing array of six Amptek XR100CR sxr detectors, each comprised of a Si photodiode, a chargesensitive preamplifier, a thermoelectric cooler, and a Cremat GSA CR200500ns having a pulse FWHM of about 1200 ns [3]. One upgrade to this system entails a CR20025ns GSA which will reduce the FWHM to 60 ns. The digitization rate is also increased from 60 MHz to 240 MHz, sufficient to resolve a 60 ns Gaussian pulse. The upgrade will also incorporate improved shielding from IGBT switching noise arising from MST’s Bt and Bp programmable power supplies. Housing the detector assembly within CompacSRFseries enclosures attenuates noise at 20 MHz by 80 dB. Initial measurements will be presented. [1] A.M.DuBois,et al.,PRL submitted [2] A.M.DuBois, et al.,RSI,86,073512(2015) [3] D.J.Clayton,et al., RSI,81,10E308(2010) [Preview Abstract] 

YP10.00070: Kinetic nonMaxwellians, from theory to experiments Olivier Izacard This contribution shows strong progresses on the analytic prediction of some kinetic effects (e.g., presence of superthermal particles) on a selection of theories which usually assume a Maxwellian distribution function (MDF). The new method developed is based on the use of nonorthogonal basis sets to represent analytic nonMaxwellian distribution functions (NMDFs). This choice is motivated by its efficiency to model experimental and numerical NMDFs computed by PIC or FokkerPlank codes and its capability to extract physical interpretation. We particularly introduce an interpreted NMDF which helped to understand the origin of the TSECE discrepancy (up to 20\% on the electron temperature due to less than 2\% of nonthermalized particles) observed in JET and TFTR. Additional results are discussed such as the inconsistency of the empirical SEE formula with a MDF, and the replacement of a diffusion adhoc coefficient by NMDFs. Finally, we show inclusion of kinetic effects in generalized fluid models and we focus our discussion on experimental perspectives toward NSTXU measurements of NMDFs with different diagnostics. A part of this work is disseminated in Refs.[1,2].\newline [1] O. Izacard, Phys. Plasmas 23, 082504 (2016) [2] O. Izacard, Submitted to J. Plasma Phys. (2016)\newline Footnote: LLNLABS702319 [Preview Abstract] 

YP10.00071: Photoionization sensor CES for noninvasive medical diagnostics Aleksandr Mustafaev, Iuliia Rastvorova, Kristina Khobnya, Sofia Podenko Method CES (collisional electron spectroscopy), patented in Russia, the USA, Japan, China, Germany and Britain, allows to analyze the gaseous mixtures using electron spectroscopy under high pressures up to atmospheric without using vacuum. The design of VUV photoionization detector was developed based on this method. Such detector is used as a portable gas analyzer for continuous personal biomedical monitoring. This detector measures energy of electrons produced in ionization with resonance photons, whose wavelength situated in the vacuum ultraviolet (VUV). Nowadays, micro plasma source of such photons on resonant line of Kr with energy of 10,6 eV is developed. Only impurities are ionized and detected by the VUVemission, meanwhile the main components of air stay neutral that reduces background signal and increases the sensibility along with accuracy. The experimental facilities with VUV photoionization sensors CES are constructed with the overall sizes about 10*10*1mm. The watt consumption may comprise less than 1W. Increase of electrometer amplifier's sensibility and more highaperture construction are used today to increase the sensibility of CESdetectors. The wide range of detectable molecules and high sensitivity allow the development of portable device, which can become the base of the future preventive medicine. [Preview Abstract] 

YP10.00072: Axial Plasma Jet Characterization on a Microsecond XPinch G.S. Jaar, R.K. Appartaim The plasma jets generated from a two wire xpinch have been studied with current quarter period of 1 $\mu$s. Wires of tungsten, aluminum, and titanium of 25100 $\mu$m thicknesses have been exploded with a peak current value of 350kA. The plasma has been characterized using Nd:YAG based schlieren photography, timeresolved optical photography, xray photodiode detector, and a flat crystal xray spectrometer. The schlieren photographs enable determination of the evolution and velocity of the jets. Plasma temperature and density measurements at the crossing point will also be reported from the crystal spectrometer. [Preview Abstract] 

YP10.00073: A multicone xray imaging Bragg crystal spectrometer. Manfred Bitter, K. W. Hill, Lan Gao, P. C. Efthimion, L. DelgadoAparicio, S. Lazerson, N. Pablant In a recent article, \textit{see }Rev. Sci. Instrum. \textbf{87}, 11E333 (2016), we described a new xray imaging Bragg crystal spectrometer, which  in combination with a streak camera or a gated strip detector  can be used for timeresolved measurements of xray line spectra at the National Ignition Facility (NIF) and other high power laser facilities. The main advantage of this instrument is that it produces perfect images of a point source for each wavelength in a selectable spectral range and that the detector plane can be inclined by an arbitrary angle with respect to the crystal surface. These unique imaging properties are obtained by bending the xray diffracting crystal into a certain shape, which is generated by arranging multiple cones with different aperture angles on a common nodal line. In this paper, we present results from optical tests of these multicone structures and numerical results on the deteriorations of the spectral and spatial resolutions that may be caused by potential misalignments of the source, crystal, and detector. [Preview Abstract] 

YP10.00074: Plasma undulator excited by highorder mode lasers. Jingwei Wang, Sergey Rykovanov A lasercreated plasma undulator together with a laserplasma accelerator makes it possible to construct an economical and extremely compact XFEL. However, the spectrum spread of the radiation from the current plasma undulators is too large for XFELs, because of the different values of strength parameters. The phase slippage between the electrons and the wakefield also limits the number of the electron oscillation cycles, thus reduces the performance of XFEL. Here we proposed a phaselocked plasma undulator created by highorder mode lasers. The modulating field is uniform along the transverse direction by choosing appropriate laser intensities of the modes, which enables all the electrons oscillate with the same strength parameter. The plasma density is tapered to lock the phase between the electrons and the wakefield, which signally increases the oscillation cycles. As a result, Xray radiation with high brightness and narrow bandwidth is generated by injecting a highenergy electron beam into the novel plasma undulator. The beam loading limit indicates that the current of the electron beam could be hundreds of Ampere. These properties imply that such a plasma undulator may have great potential in compact XFELs. [Preview Abstract] 

YP10.00075: Spaceresolved K$\alpha $ emission measurement of warm dense titanium targets irradiated by intense laser pulses Leejin Bae, Minsang Cho, Gyeongbo Kang, Minju Kim, Young Hoon Kim, Jongwon Lee, Byoungick Cho, Ulf Zastrau Measurements of characteristic innershell K$\alpha $ emission have been widely used and reliable spectroscopic plasma diagnostics. Intense laserplasma interactions on the solid target generate multiple electron distributions, i.e. hot relativistic and low energy bulk electrons. The bulk electrons create warm dense (10 \textasciitilde 100 eV and solid density) conditions in titanium foil and induce the shifts of K$\alpha $ emission spectra by creating Mshell vacancies. Therefore, modified K$\alpha $ emission spectra can be served as a bulk electron temperature. In this contribution, we present the titanium K$\alpha $ imaging spectroscopy experiment using a toroidally bent crystal, and the Kshell emission spectrum simulations using the collisionalradiative code SCFLY, for various bulk electron temperatures. The spatial distribution of electron temperature in the titanium foil which is irradiated by an intense laser pulse could be obtained, and possible electron transport mechanism will be discussed. [Preview Abstract] 

YP10.00076: Nonlinear Absorption of Xray Free Electron Laser Pulses in Dense Aluminum Plasmas Min Sang Cho, M. Kim, H.K. Chung, Byoungick Cho XFEL provides unique opportunities to generate and investigate dense plasmas. Here, we present the intensity dependent, nonlinear xray absorption in dense aluminum target using the collisionalradiative population kinetic calculations. With high peak intensity of XFEL pulses, even below Kabsorption edge, xray photons could create excited states of which absorption is larger than the ground state absorption. At the resonant energy of neutral atom, increasing xray absorption in the intensity range of 1016\textasciitilde 17 W/cm2 has been observed, and it is the reverse saturable absorption in the xray regime. The similar observations have been also made at the other resonant energies of higher charge states. At even higher XFEL intensities, bleaching a specific charge state could lead a transition from reverse saturable absorption to saturable absorption, so thus xray absorption is decreasing. Detailed population kinetics of charge states relevant to the absorption of xray photons, and fast modulation of XFEL spectrum will be discussed. [Preview Abstract] 

YP10.00077: Effects of laser polarization on electrostatic shock ion acceleration in nearcritical plasmas YoungKuk Kim, Teyoun Kang, Min Sup Hur Collisionless electrostatic shock ion acceleration has become a major regime of laserdriven ion acceleration owing to generation of quasimonoenergetic ion beams from moderate parametric conditions of lasers and plasmas in comparison with targetnormalsheathacceleration or radiation pressure acceleration. In order to construct the shock, plasma heating is an essential condition for satisfying Mach number condition 1.5 \textless M \textless 3.7, where M$=$v/c$_{\mathrm{s}}$ and c$_{\mathrm{s}}$ is the sound speed. Recently we showed that the shock ion acceleration could be achieved via electron heating by relativistic transparency of a circularly polarized (CP) laser pulse. This is different from the usual method of shock generation via the electron heating by oscillating ponderomotive force of a linearly polarized laser pulse. In this poster we show onedimensional particleincell simulation result to compare LPshock with CPshock ion acceleration for a broad range of parameters. As the main result, the CPshock could be formed at lower density plasmas than the LPshock due to the efficient density compression of CP pulses. This leads to higher shock velocity and ion energy. Comparison of other detailed characteristics such as transmittance, scale length dependence, and other results from the simulations is presented. In addition, twodimensional simulation is also discussed in association with Weibel instability. [Preview Abstract] 

YP10.00078: Effect of the cross frequency on the transport in the fusion plasmas ChanYong An, Byunghoon Min, ChangBae Kim The cross phase $\delta$, i.e. the difference of the phase between the electric potential $\phi$ and the pressure $p_e$, is studied in the electromagnetic resistive drift turbulence. An evolution equation for $\delta$ is obtained in the Fourier space that includes the energynontransporting fluxes due to $E\times B$ and magnetic nonlinearities. BOUT++ platform [1] is used for the simulation until the steady state of the model is reached. The thermal transport $\Gamma$ is found to be proportional to $p_e^2 \cdot \delta$ and $\dot{\delta}$ is much smaller than the frequencies of $\phi$ and $p_e$. The effect of zonal flows on $\delta$ will be presented at the conference. [1] B. D. Dudson, M. V. Umansky, X. Q. Xu, P. B. Snyder, and H. R. Wilson, Comp. Phys. Comm. 180 1467 (2009) [Preview Abstract] 

YP10.00079: Study of the cross phase in the ion temperature gradient driven turbulence Byunghoon Min, ChanYong An, ChangBae Kim The evolution of cross phase, that is the phase difference between the electric potential and the pressure, is examined in the electrostatic ion temperature gradient fluid turbulence. It is important to study cross phase because the thermal transport is roughly proportional to cross phase. The evolution equation of cross phase is derived in a similar way as the energy evolutions are found in the Fourier space. Threedimensional fluid simulations are performed in the BOUT++ platform [1] with the shifted metric coordinate system. It is found that the linear and nonlinear contributions to $\partial_t \delta^2$ change signs as the fluctuations become saturated and they add up to make $\delta^2$ steady. Effects of zonal flow on cross phase are investigated and will be discussed at the conference. [1] B. D. Dudson, M. V. Umansky, X. Q. Xu, P. B. Snyder, and H. R. Wilson, Comp. Phys. Comm. 180 1467 (2009). [Preview Abstract] 

YP10.00080: Effects of 2D and 3D Error Fields on the SAS Divertor Magnetic Topology G.L. Trevisan, L.L. Lao, E.J. Strait, H.Y. Guo, W. Wu, T.E. Evans The successful design of plasmafacing components in fusion experiments is of paramount importance in both the operation of future reactors and in the modification of operating machines. Indeed, the Small Angle Slot (SAS) divertor concept, proposed for application on the DIIID experiment, combines a small incident angle at the plasma strike point with a progressively opening slot, so as to better control heat flux and erosion in highperformance tokamak plasmas. Uncertainty quantification of the error fields expected around the striking point provides additional useful information in both the design and the modeling phases of the new divertor, in part due to the particular geometric requirement of the striking flux surfaces. The presented work involves both 2D and 3D magnetic error field analysis on the SAS strike point carried out using the EFIT code for 2D equilibrium reconstruction, V3POST for vacuum 3D computations and the OMFIT integrated modeling framework for data analysis. An uncertainty in the magnetic probes’ signals is found to propagate nonlinearly as an uncertainty in the striking point and angle, which can be quantified through statistical analysis to yield robust estimates. [Preview Abstract] 

YP10.00081: Analysis of Alfven Eigenmodes destabilization by fast particles in Large Helical Device Jacobo Varela, Donald Spong, Luis Garcia Fast particle populations in nuclear fusion experiments can destabilize Alfven Eigenmodes through inverse Landau damping and couplings with gap modes in the shear Alfven continua. We use the reduced MHD equations to describe the linear evolution of the poloidal flux and the toroidal component of the vorticity in a full 3D system, coupled with equations of density and parallel velocity moments for the energetic particles. We add the Landau damping and resonant destabilization effects by a closure relation. We apply this model to study the Alfven modes stability in Large Helical Device (LHD) equilibria for inward configurations, performing a parametric analysis along a range of realistic values of fast particle $\beta $ ($\beta $fp), ratios of thermal/Alfven velocities (Vth/Vao), magnetic Lundquist numbers (S) and dominant toroidal (n) modes families. The n $=$ 1 and n $=$2 toroidal families show the largest growth rates for parameters closer to a real LHD scenario (S $=$ 5E6, $\beta $fp $=$ 0.02 and Vth/Vao $=$ 0.5), particularly the modes n/m $=$ 1/2 and 2/4 located the inner and middle plasma ($\rho \quad =$ 0.25  0.5 with $\rho $ the normalized minor radius). The n $=$ 3 and n $=$ 4 toroidal families are weakly perturbed by fast particles. [Preview Abstract] 

YP10.00082: Tunable PlasmaWave Laser Amplifier. J. Bromage, D. Haberberger, A. Davies, S. Bucht, J.D. Zuegel, D.H. Froula, R. Trines, R. Bingham, J. Sadler, P.A. Norreys Raman amplification is a process by which a long energetic pump pulse transfers its energy to a counterpropagating short seed pulse through a resonant electron plasma wave. Since its conception, theory and simulations have shown exciting results with up to tens of percent of energy transfer from the pump to the seed pulse. However, experiments have yet to surpass transfer efficiencies of a few percent. A review of past literature shows that largely chirped pump pulses and finite temperature wave breaking could have been the two most detrimental effects. A Raman amplification platform is being developed at the Laboratory for Laser Energetics where a combination of a highintensity tunable seed laser\footnote{S. Bucht \textit{et al}., ``Transforming the Idler for Use in LaserPlasma Interaction Experiments,'' this conference. } with sophisticated plasma diagnostics (dynamic Thomson scattering\footnote{ A. Davies \textit{et al}., ``Dynamic Thomson Scattering from Nonlinear Electron Plasma Waves in a Raman Plasma Amplifier,'' this conference.}) will make it possible to find the optimal parameter space for highenergy transfer. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DENA0001944. [Preview Abstract] 

YP10.00083: Accordion effect in a laser wakefield accelerator: Generating comblike electron beams for a tunable pulsed source of polychromatic gammarays. Serge Kalmykov, Xavier Davoine, Isaac Ghebregziabher, Bradley Shadwick Trains of synchronized, fslength GeVscale electron bunches with a submicron normalized transverse emittance, brightness up to 10$^{17}$ A/m$^2$, and controlled energy spacing may be purposely produced in both plasma channels and uniform plasmas. A cavity of electron density, driven by an optimally designed multicolor stack of 10TWscale laser pulses, experiences expansions and contractions, periodically injecting electrons from the ambient dense plasma, accelerating them without compromising the beam quality [1]. This periodic injection is naturally achieved in a plasma channel [2]. The channel, however, is not a prerequisite to this effect. The number of comb components, as well as their charge and energy spacing, can be controlled in a uniform plasma by independently varying focal spots of the laser stack components. Inverse Thomson scattering from these comblike beams produces synchronized sequences of quasimonochromatic, fslength gammaray flashes, which may become an asset to pumpprobe experiments in dense plasmas. [1] S. Y. Kalmykov et al., Phys. Plasmas 22, 056701 (2015). [2] S. Y. Kalmykov et al., Plasma Phys. Control. Fusion 58, 034006 (2016). [Preview Abstract] 

YP10.00084: Measurements and simulations of ICRF induced plasma convection in front of the 3strap antennas in ASDEX Upgrade Wei Zhang Plasma heating with waves in the Ion Cyclotron Range of Frequency (ICRF) is one of the standard heating methods in tokamaks. The parallel (to the magnetic field) component of the electric field of the waves enhances the edge plasma potential nonlinearly through radiofrequencysheath (rfsheath) rectification. The gradient of this potential across magnetic field drives plasma convection in the ScrapeOff Layer. To reduce the rfsheath driven close to ICRF antennas, the parallel electric nearfield has to be decreased. This can be achieved by minimization of undesired parasitic currents induced in the antenna box by the antenna currents. New antennas with a novel approach to reduce those undesired currents through the proper phase and amplitude of the current in 3straps have been installed and validated on ASDEX Upgrade. With reflectometers embedded in one 3strap antenna at different poloidal locations, the density profiles in front of the antenna can be measured in when the antenna is either active or passive. The ICRF induced edge plasma convection in different antenna feeding configurations (different phasing, different power ratio between the central and the side straps) has thus been studied. Also we have carried out comprehensive simulations by running the EMC3{\}EIRENE, RAPLICASOL and SSWICH codes in an iterative and quasi selfconsistent way. The steady{\}state ICRF induced plasma density convection can clearly be reproduced in the models and compared with the ones measured in experiments. [Preview Abstract] 

YP10.00085: Modelling of ionacoustic shocks with reflected ions Adrian Hanusch, Tatyana Liseykina In the studies of electrostatic shocks a distinction is made between electrons, that freely pass the shock structure and those that get trapped into the shock potential. If the width of the trapping region in velocity space is bigger than the change of the electron velocity by collisions over the evolution time of the trapping potential, the captured electrons are better described by the adiabatic trapping model. In the opposite case electrons remain Maxwellian. Which model is suitable in the real situation depends on how the shock is generated: adiabatic trapping is used for the shock generated in the piston tube, while Boltzmannian  in the shock tube. Recently the selfregulated ion reflection and acceleration in ionacoustic shocks for both electron models was studied analytically [M. Malkov et al. PoP 23, 2016]. Here we present the numerical study of electrostatic shocks generated by reflection of a highspeed plasma off a conducting wall and by the decay of plasma density discontinuity. Different assumptions for the electron distribution are compared to the fully kinetic simulations. Special attention is given to the shock reflected ions. The finite ion temperature effect on the shock electrostatic structure and ion reflection efficiency is analyzed. [Preview Abstract] 

YP10.00086: Higherdimensional catastrophes in nonlinear Compton scattering. Vasily Kharin, Daniel Seipt, Sergey Rykovanov The Compton scattering of the light on the accelerated electron beam is a valuable tool for generating tunable wide range X and $\gamma$radiation.However, the crosssection of the scattering is relatively low. That is, in order to obtain bright Xrays one naturally may consider increasing the intensity of the incident light. Passing to relativistic values of laser intensity significantly changes scattering mechanism. Precise QED analysis of the scattered spectra leads to the study of the corresponding elements of $S$matrix. Evaluation is usually performed numerically (except cases of specific pulse shapes and scattering angles). We argue that the problem of extracting the scattered spectra in nonlinear Compton scattering of the pulse can be reformulated in terms of studying properties of projection map of specific surfaces associated to the pulse. They are stable with respect to initial conditions, and the brightest regions of the spectrum appear to be in correspondence with the singularities of the projection map, also known as caustics in pure mathematics, diffraction optics and cosmology. [Preview Abstract] 

YP10.00087: Attosecond Control of Relativistic Electron Bunches using TwoColour Fields Sergey Rykovanov, Mark Yeung, Jana Bierbach, Lu Li, Erich Eckner, Stephan Kuschel, Abel Woldegeorgis, Christian Roedel, Alexander Saevert, Gerhard Paulus, Mark Coughlan, Brendan Dromey, Matt Zepf Energy coupling during relativistically intense lasermatter interactions is encoded in the attosecond motion of strongly driven electrons at the preformed plasmavacuum boundary. Studying and controlling this motion can reveal details about the microscopic processes that govern a vast array of lightmatter interaction physics and applications. These include research areas right at the forefront of extreme laserplasma science such as laserdriven ion acceleration1, bright attosecond pulse generation and efficient energy coupling for the generation and study of warm dense matter. Here we experimentally demonstrate that the precise addition of a second laser beam operating at the second harmonic of the driving laser pulse can lead to attosecond control over the trajectories of relativistic electron bunches formed during such interactions. Significant enhancements in the resulting high harmonic yield were observed with potential applications as a source of ultrabright, extremeultraviolet attosecond radiation for atomic and molecular pumpprobe experiments. [Preview Abstract] 

YP10.00088: Fluid electron and gyrokinetic ion simulation for tearing mode Dongjian Liu, Jian Bao, Zhihong Lin A finite mass electron fluid model have been developed to study the low frequency electromagnetic modes in magnetized plasmas[1]. Coupled to the gyrokinetic ions, the global gyrokinetic particle simulation of tearing modes have been developed and verified in the gyrokinetic toroidal code (GTC). GTC linear simulations in the fluid limit of the kinktearing, resistive tearing modes and collisonless tearing mode in the cylindrical geometry agree well with the magnetohydrodynamic eigenvalue and initial value codes. Ion kinetic effects are found to reduce the radial width of the tearing modes. GTC simulations of the resistive tearing modes in the toroidal geometry find that the toroidicity reduces the growth rates[2]. Reference: [1] Dongjian Liu and Liu Chen, 2011, Plasma Physics and Controlled Fusion, 53 062002 [2] Dongjian Liu, Wenlu Zhang, Joseph McClenaghan, Jiaqi Wang and Zhihong Lin, 2014, Physics of Plasmas 21,122520. [Preview Abstract] 

YP10.00089: Simulation study of core heating properties for recent FIREXI experiments Tomoyuki Johzaki, Yusuke Kai, Takuma Endo, Hideo Nagatomo, Atsushi Sunahara, Yasuhiko Sentoku, Toshihiro Taguchi, Shinsuke Fujioka, Hiroyuki Shiraga, Hiroshi Azechi The demonstration of efficient core heating is the main purpose of FIREXI project, where Au coneattached solid ball CD target is used. For the guiding of fast electron beam generated by relativistic laser plasma interactions, the kiloTeslaclass longitudinal magnetic field is applied by a capacitorcoil target and kJclass nsdurration high power laser. In addition, to reduce the collisional effect (energy loss and scattering of fast electrons) during propagation in the Au cone tip, we introduced openedtip cone (tipless cone). To evaluate the core heating properties, we carried out the integrated simulations, which shows the enhancement of core heating efficiency due to the magnetic guiding and openedtip cone by a factor of three. These simulation results will be shown and be compared with the experimental results. [Preview Abstract] 

YP10.00090: Analyzing neutron timeofflight spectra from the National Ignition Facility using moments R. Hatarik, J. Field, M. Eckart, G. Grim, E. P. Hartouni, A. Moore, D. Munro, D. Sayre The neutron spectrum produced by an indirectly driven implosion at the National Ignition Facility (NIF) provides valuable insight into the performance of the capsule. There are four neutron timeofflight (nTOF) spectrometers being used at the NIF which can simultaneously measure DD and DT fusion neutrons on NIF shots. The width of theses peaks have been traditionally associated with the temperature of the plasma, recent work shows that it has to be considered a combination of flow and temperature distributions. This leads to a deviation from a pure gaussian shape of a single temperature static plasma and the presence of higher order moments in the neutron spectrum. The current status of the analysis of neutron spectra from the nTOF diagnostics at the NIF will be presented. [Preview Abstract] 

YP10.00091: Application of the Disruption Predictor Feature Developer to developing a machineportable disruption predictor Matthew Parsons, William Tang, Eliot Feibush Plasma disruptions pose a major threat to the operation of tokamaks which confine a large amount of stored energy. In order to effectively mitigate this damage it is necessary to predict an oncoming disruption with sufficient warning time to take mitigative action. Machine learning approaches to this problem have shown promise but require further developments to address (1) the need for machineportable predictors and (2) the availability of multidimensional signal inputs. Here we demonstrate progress in these two areas by applying the Disruption Predictor Feature Developer to data from JET and NSTX, and discuss topics of focus for ongoing work in support of ITER. [Preview Abstract] 

YP10.00092: Pressure tensor dynamics in the fluid description of Weibeltype instabilities Mathieu Sarrat, Daniele Del Sarto, Alain Ghizzo The study of Weibeltype instabilities triggered by temperature or momentum anisotropy normally requires a full kinetic treatement, though reduced kinetic models often provide an efficient alternative, both from a computational point of view and thanks to a simplified analysis that helps a better physical insight. We here show how, similarly to reduced kinetic models, an extended fluid model including the full pressure tensor dynamics [1,2] provides a consistent description of Weibeltype modes in presence of two counterstreaming, nonrelativistic beams with initially anisotropic pressures: focussing on propagation transverse and parallel to the beams we discuss the fluid dispersion relation of Weibel InstabilityCurrent Filamentation Instability coupled modes [2] and of the time resonant Weibel instability [3]. This fluid analysis is shown to agree with the kinetic result and to allow the identification of some thermal effects, whose interpretation appeared more difficult in full kinetic descriptions.\\ \\$[1]$ B. Basu, Phys. Plasmas 9, 5131 (2002) [2] M. Sarrat, D. Del Sarto, A. Ghizzo, EPL, 115, 45001 (2016) [3] M. Sarrat, D. Del Sarto, A. Ghizzo, to be submitted. [Preview Abstract] 

YP10.00093: NIF laboratory astrophysics simulations investigating the effects of a radiative shock on hydrodynamic instabilities A.A. Angulo, C.C. Kuranz, R P. Drake, C. M. Huntington, H. S. Park, B.A. Remington, D. Kalantar, S. MacLaren, K. Raman, A. Miles, Matthew Trantham, J.L. Kline, K. Flippo, F.W. Doss, D. Shvarts This poster will describe simulations based on results from ongoing laboratory astrophysics experiments at the National Ignition Facility (NIF) relevant to the effects of radiative shock on hydrodynamically unstable surfaces. The experiments performed on NIF uniquely provide the necessary conditions required to emulate radiative shock that occurs in astrophysical systems. The corecollapse explosions of red supergiant stars is such an example wherein the interaction between the supernova ejecta and the circumstellar medium creates a region susceptible to RayleighTaylor (RT) instabilities. Radiative and nonradiative experiments were performed to show that RT growth should be reduced by the effects of the radiative shocks that occur during this corecollapse. Simulations were performed using the radiation hydrodynamics code Hyades using the experimental conditions to find the mean interface acceleration of the instability and then further analyzed in the buoyancy drag model to observe how the material expansion contributes to the mixlayer growth. [Preview Abstract] 

YP10.00094: ABSTRACT WITHDRAWN 

YP10.00095: E X B instability with sheared magnetic field Salil Das, Shahin Nasrin, Mridul Bose The crossfield instability is ubiquitous in all electromagnetic systems. Effect of this instability is studied rigorously in plasma system with steady external magnetic field. Therefore, we have considered a sheared magnetic field to study the E X B instability which is observed in the internal transport barrier of fusion machines. Depending on the relation between y {\&} L$_{\mathrm{S\thinspace }}$we have considered three different regimes. The response of the magnetic shear, i.e. y/L$_{\mathrm{S}}$, (where, y is the magnitude of the applied magnetic field along ydirection and L$_{\mathrm{S\thinspace }}$is the shear length) is then estimated which shows few interesting features. [Preview Abstract] 

YP10.00096: ABSTRACT WITHDRAWN 

YP10.00097: Dynamics of Ion Beam Charge Neutralization by Ferroelectric Plasma Sources. Anton D. Stepanov, Erik P. Gilson, Larry R. Grisham, Igor D. Kaganovich, Ronald C. Davidson, Qing Ji, Arun Persaud, Peter A. Seidl, Thomas Schenkel Ferroelectric Plasma Sources (FEPSs) can generate plasma that provides effective spacecharge neutralization of intense highperveance ion beams. Here we present experimental results on charge neutralization of a highperveance 38 keV Ar$^{\mathrm{+}}$ beam by a FEPS plasma. By comparing the measured beam radius with the envelope model for spacecharge expansion, it is shown that a charge neutralization fraction of 98{\%} is attainable. The transverse electrostatic potential of the ion beam is reduced from 15 V before neutralization to 0.3 V, implying that the energy of the neutralizing electrons is below 0.3 eV. Nearcomplete charge neutralization is established $\sim $5$\mu $s after the driving pulse is applied to the FEPS, and can last for 35 $\mu $s. It is argued that the duration of neutralization is much longer than a reasonable lifetime of the plasma produced in the sub$\mu $s surface discharge. Measurements of current flow in the driving circuit of the FEPS suggest that plasma can be generated for tens of $\mu $s after the high voltage pulse is applied. This is confirmed by fast photography of the plasma in the 1meter long FEPS on NDCXII, where effective charge neutralization of the beam was achieved with the optimized FEPS timing. [Preview Abstract] 

YP10.00098: Deuterium uptake in boronized ATJ graphite walls of NSTXU Javier Dominguez, Felipe Bedoya, Predrag Krstic, Jean Paul Allain, Stephan Irle, Charles Skinner, Robert Kaita, Bruce Koel We present a study of the role of boron and oxygen in the chemistry of deuterium retention in boronized ATJ graphite irradiated by a deuterium plasma. The experimental results were obtained by the first in vacuo Xray Photoelectron Spectroscopy (XPS) measurements at the National Spherical Torus Experiment Upgrade (NSTXU). The subtle interplay of boron, carbon, oxygen and deuterium chemistry is explained by reactive molecular dynamics simulation, verified by quantumclassical molecular dynamics and successfully compared to the measured data. The calculations deciphered the roles of oxygen and boron for the deuterium retention and predict deuterium uptake by a boronized carbon surface of 90{\%} close in value to that previously predicted for a lithiated and oxidized carbon surface. [Preview Abstract] 

YP10.00099: Dretention and sputtering of simultaneously lithiated and boronized carbon surfaces in NSTXU Predrag Krstic, Javier Dominguez While lithium serves as a catalyzer for high oxygen concentration in the surface of the lithiated graphite, and oxygen is performing the retention chemistry of D, boron effectively suppresses the role of oxygen and takes over the deuterium retention chemistry. Interestingly, lithium and boron are concurrent players for retention chemistry in LiBC surfaces. In presence of oxygen, lithium role is suppressed with boron and oxygen being concurrent player in the D retention chemistry. With increase of the deuterium accumulation, the oxygen takes over the dominant role in retention. XPS \textit{in vacuo} data taken in the NSTXU with the MAPP probe were used to characterize the PFCs chemistry and to provide a comparison with the results from the simulations. [Preview Abstract] 

YP10.00100: NonAxisymmetric Disruption SOL Current Measurement In DIIID Plasmas Joshua Cabrera, J. Hanson, G. Navratil, J. Bialek J. Cabrera, J. Hanson, G. Navratil, J. Bialek, Columbia U–During tokamak disruptions known as vertical displacement events (VDEs) currents which flow between the plasma core and plasma facing components can reach nearly 20$\%$ of the total plasma current. These scrape off layer (SOL) currents are thought to affect the dynamics of plasma disruption. We have made use of an array of tile current monitors installed on the DIIID tokamak to perform low toroidal mode number (n$\le$2) analysis on SOL currents from such VDEs. In all cases examined (over 30 shots) currents exhibited toroidal asymmetry with toroidal peaking factor $\sim$2. Strong initial peaking in n=1 current measurements are correlated with n=1 magnetic fluctuations during VDEs. Following the peak SOL current and after observation of the final last closed flux surface (LCFS), n=1 mode activity $\sim$20$\%$ of n=0 peak amplitude persists for $\sim$10ms. Predictions from the VALENIVB simulation code utilizing current profile reconstructions from magnetic sensor array measurements will be compared with SOL current measurements. Possible effects of these SOL currents on plasma dynamics during disruption are considered. [Preview Abstract] 

YP10.00101: Effects of radio frequency fields in the lower hybrid range on temperature gradient driven driftmodes in tokamaks: Momentum and impurity transport Salil Das, Hogun Jhang, R. Singh, H. Nordman The significant effect of impurities in radiation losses and plasma dilution, which result in lower fusion power, and the evaluation of the important effects of intrinsic rotation on transport barrier formation, determination of momentum pinch velocity and its theoretical basis, in tokamak performance is studied using the fourwave parametric process using an electrostatic, collisionless fluid model for iontemperaturegradient and trappedelectron mode driven turbulence in the presence of radio frequency fields in the lower hybrid (LH) range of frequencies. The beating of the pump and the sidebands exert a ponderomotive force on electrons, modifying the eigenfrequency of the drift~waves~and influencing the growth rates and the turbulent transport properties. Explicit expressions for the nonlinear growth rate and the associated ion thermal conductivity~and effective~impurity diffusivity~are derived. The effects of the rf fields on the~momentum and impurity transport~coefficients are evaluated for~key parameters like~rf power, temperature gradients, and magnetic shear. [Preview Abstract] 

YP10.00102: Universe of constant Han Yongquan The ideal gas state equation is not applicable to ordinary gas, it should be applied to the Electromagnetic "gas" that is applied to the radiation, the radiation should be the ultimate state of matter changes or initial state, the universe is filled with radiation. That is, the ideal gas equation of state is suitable for the Singular point and the universe. Maybe someone consider that, there is no vessel can accommodate radiation, it is because the Ordinary container is too small to accommodate, if the radius of your container is the distance that Light through an hour, would you still think it can't accommodates radiation? Modern scientific determinate that the radius of the universe now is about 10$^{\mathrm{27}}$ m, assuming that the universe is a sphere whose volume is approximately: V $=$ 4.19 × 10$^{\mathrm{81}}$ cubic meters, the temperature radiation of the universe (cosmic microwave background radiation temperature of the universe, should be the closest the average temperature of the universe) T $=$ 3.15k, radiation pressure P $=$ 5 × 10$^{\mathrm{6}}$ N / m $^{\mathrm{2}}$, according to the law of ideal gas state equation, PV / T $=$ constant $=$ 6 × 10$^{\mathrm{75}}$, the value of this constant is the universe, The singular point should also equal to the constant Author: hanyongquan [Preview Abstract] 

YP10.00103: Fast Tunable Microwave Devices Using Selfdriven Plasma Instabilities David Biggs, Mark Cappelli Tunable electromagnetic devices using plasmas are of interest for various applications such as high frequency communications and analog signal processing. At microwave frequencies of tens of gigahertz, lowpressure plasmas must be employed in order to avoid high wave damping from collisions. The drawback of lowpressure plasmas is that their diffusion timescales are long, on the order of hundreds of microseconds. Other mechanisms than diffusion must be employed to achieve fast tuning capabilities of these devices. One candidate mechanism is to use a selfdriven plasma instability, which may allow for fast tuning of microwave resonant cavities. In this work, a microwave resonant cavity is studied consisting of a rectangular waveguide with two conducting posts spaced along the propagation direction to form a rectangular cavity. The cavity acts as a band pass filter and transmits microwave signals around its resonant frequency. Plasma may be introduced into the cavity between the conducting posts in order to change the refractive index and thus the resonant and transmission frequency of the device. The location of the plasma and its plasma density are important parameters in determining the resonant frequency, and both parameters are capable of being tuned with plasma instabilities. [Preview Abstract] 
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