Bulletin of the American Physical Society
2005 APS April Meeting
Saturday–Tuesday, April 16–19, 2005; Tampa, FL
Session L1: Poster Session II |
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Room: Marriott Tampa Waterside Florida Salon IV-V |
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L1.00001: NEW PRECISION MEASUREMENT METHODS
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L1.00002: Optically pumped helium-3 NMR in a Penning trap system Xiang Fei The magnetic moment ratio of the shielded helion to the nuclear magneton can be measured by comparing the helium-3 NMR frequencies with the proton cyclotron frequencies in a Penning trap system. Cyclotron frequencies of other ions and electrons may also be used for comparison. Important physical constants could be obtained by using available (for example, the proton- to-electron mass ratio, the electron g-factor, and the magnetic moment ratio of the shielded helion to the shielded proton) and proposed (g-factor of the proton and antiproton) high precision NMR and Penning trap measurements. The goal of this experiment is to determine the shielded proton magnetic moment in Bohr magnetons, the diamagnetic shielding correction for protons in water, and other magnetic moment ratios involving electrons and protons to the 5 ppb level of accuracy with possible improvements to 1 ppb level. [Preview Abstract] |
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L1.00003: Analytical modeling of high precision measurement of thermal heat transfer by laser heating Abhishek Jain Study of precise thermal heat transfer due to laser heating of metals and other structures has been found to be of great use in different applications ranging from MEMS, nanostructures and biomedical devices. In this paper an analytical modeling of measuring the temperature at a junction of the thermocouple and the metal surface is done. Analytical treatment is also done to calculate the temperature distribution inside the metal assuming the laser as a point heat source. The metal in consideration is stainless steel and is heated using laser. When a thermocouple is mounted on the metal surface there is a fall in the junction temperature due to the depression of the thermocouple inside the metal, which results in the error in the final measurement. In the present study an analytical investigation is done to measure the error generated due to this depression. Temperature distribution inside the block is also calculated based on heat diffusion equation in cylindrical coordinates. [Preview Abstract] |
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L1.00004: Nonlinear optical properties of CdS1-xSex crystallites-doped glass in femtosecond time-scale. SeongMin Ma, L. Creekmore, K. Lee, Qiguang Yang, J. T. Seo, T. Skyles, H. Brown, A. Jackson, B. Tabibi We report the nonlinear optical properties of CdS1-xSex crystallites doped in glass measured with a 150 fs Ti:Sappire laser at 775 nm wavelength. The nonlinear absorption and nonlinear refraction coefficients were measured to be $1\times 10^{-20}$ m$^{2}$/W and $7\times 10^{-15}^{ }$W/m , respectively, by using a single beam Z-scan nonlinear spectroscopy technique. Experimental data is theoretically fitted and discussed. The dominant physical origin of the optical nonlinearity of the material is two-photon resonant electronic process. The large nonlinearity indicates CdS1-xSex crystallite doped glass is an excellent candidate for photonic applications, such as defense for homeland security, battlefield enhancements, optical switching, and pulse shaping. [Preview Abstract] |
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L1.00005: Precision Penning Trap Mass Spectrometry of S, Kr and Xe Matthew Redshaw, Wei Shi, Edmund Myers Using a phase coherent technique to measure the cyclotron frequency of single ions in a Penning trap [1], we have performed mass measurements on $^{32}$S and the two most abundant krypton and xenon isotopes $^{84}$Kr, $^{86}$Kr, $^ {129}$Xe and $^{132}$Xe, to relative precisions of 0.1 ppb. This is a factor of $\sim$10-100 improvement in precision over current values [2]. [1] M.P. Bradley, J.V. Porto, S. Rainville, J.K. Thompson, and D.E. Pritchard, PRL \textbf{83}, 4510 (1999). [2] G. Audi, A.H. Wapstra, and C. Thibault, Nucl Phys \textbf{A729}, 337 (2003). [Preview Abstract] |
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L1.00006: NUCLEAR PHYSICS
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L1.00007: Checker Board Model Theodore Lach The Checker Board Model (CBM) is a 2D model of the nucleus that proposes that the synchronization of the 2 outer rotating quarks in the nucleons accounts for magnetic moment of the nucleons and that the magnetic flux from the nucleons couples (weaves) into the 2D checker board array structures and this magnetic coupling in addition to electrostatic forces of the rotating and stationary quarks accounts for the apparent strong nuclear force. The symmetry of the He nucleus helps explain why this 2D structure is so stable. This model explain the mass of the proton and neutron, along with their magnetic moments and their absolute and relative sizes in terms of the above structure and predict the masses of two newly proposed quarks, the ``up'' and the ``dn'' quarks. Since the masses of the ``up'' and ``dn'' quark determined by the CBM (237.31 MeV and 42.392 MeV respectively) did not fit within the standard model as candidates for u and d, a new model (New Physics) had to be invented. This new particle physics model predicts that nature has 5 generations not 3. (1). T.M. Lach, Checkerboard Structure of the Nucleus, Infinite Energy, Vol. 5, issue 30, (2000). (2). T.M. Lach, Masses of the Sub-Nuclear Particles, nucl-th/0008026, @http://xxx.lanl.gov/ [Preview Abstract] |
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L1.00008: Detection of \v Cerenkov Light with Wavelength Shifting Plastic -- A Beam Test Brian Beckford, Naipy Perez, Joerg Reinhold The collection efficiency for \v Cerenkov light incident on a wavelength shifting plate has been determined during a beam test at the proton synchrotron at KEK. An efficiency of roughly 50\% has been determined for photons created in a fused silica radiator in front of an acrylic plate that contained a wavelength shifting fluorescent substance. The experimental procedure and the results will be presented together with possible applications for \v Cerenkov detectors. [Preview Abstract] |
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L1.00009: Dose Rate Calculations of Spent MTR-HEU Fuel Elements of the IAN-R1 Research Reactor Jose Antonio Sarta Fuentes, Luis Alvaro Castiblanco Bohorquez With cooperation of the International Atomic Energy Agency (IAEA) and the Department of Energy (DOE) of the United States, several tasks related to the waste disposal of spent MTR fuel enriched nominally to 93{\%} were carried out for the conversion of the IAN-R1 Research Reactor from MTR-HEU fuel to TRIGA-LEU fuel. In order to remove the spent MTR-HEU fuel of the core and store it safetly, a program was established at the Instituto de Ciencias Nucleares y Energ\`{\i}as Alternativas (INEA). This program included training, acquisition of hardware and sofware, design and construction of a decay pool, transfer of the spent HEU fuel elements into the decay pool and his final transport to Savanah River in United States. In this paper are presented external dose rates which were calculated for a standard spent MTR-HEU fuel element of the IAN-R1 Research Reactor. The calculations take in consideration the activity due to contributions of fission, activation and actinides products for each relevant radionuclide present in a standard spent MTR-HEU fuel. The datas obtained were the base for the respective dosimetric evaluations in the transfering operations of fuel elements into the decay pool and for shielding calculations in designing of the decay pool. [Preview Abstract] |
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L1.00010: Explanation of the symmetric fission mode of 258Fm, 260Md and 270Sg Genevieve Mouze, Christian Ythier In the 258Fm case (1), only the fragment pairs 128Sn-130Sn and 126Sn-132Sn have, in spite of a correction for spherical nuclei, a Coulomb barrier smaller than the corresponding energy- releases of 253.794 and 252.295 MeV. The resulting absence of a barrier for the fission of 258Fm into these two pairs explains the enhancement of the fission yield of Sn- fragments of mass 126,128,130 and 132 and thus the f.-w.- h.-m. of only 8 u of the A = 129 peak of the mass distribution. For 257Fm, the appearance of a symmetric mode is due to the small Coulomb barrier of the pair 128Sn-129Sn, having an energy-release of 252.517 MeV. For 270Sg (2), several fragment pairs with neutron numbers 82 have a Coulomb barrier smaller than the corresponding energy-release. This conclusion throws a new light on what can be called a fission barrier of the first kind, where the major role is played by the electrostatic properties of individual binary configurations and not by the lack of activation energy of a primordial dinuclear system. 1 D.C. Hoffman et al., Los Alamos Report LA-UR-77, 2901 (1977). 2 M.G. Itkis, Intern. Nucl. Phys. Conf.Paris, 1998, Abstr. Contrib. Papers, p.579. [Preview Abstract] |
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L1.00011: PARTICLES AND FIELDS
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L1.00012: Magnetic Flux Quanta (Fluxons) as Elementary Fermions Shegeji Fujita, Yunus Kumek, Lubna Peerzada, Salvador Godoy The electric (magnetic) field is a vector (pseudo- vector). The quanta for the electric (magnetic) fields are called the photons (fluxons). The photons can be created or annihilated, and hence they are bosons. The magnetic flux lines cannot terminate at sinks, and hence the corresponding fluxons are fermionic. The basic particle property (count- ability) of the fluxons is known as Onsager's flux quantization. We assume that the fluxons are half-spin fermions with no mass and no charge. In the presence of a magnetic field the classical electron spirals about the field. Quantum mechanically a transition from the momentum state at a zero field to the circulating Landau state at a finite field requires a perturbation. In a 2D solid such as GaAs/AlGaAs there are phonons arising from the longitudinal ionic-lattice vibrations. We assume the phonon exchange between the electron and the fluxons for the perturbation. The composite (c-) particle made of an electron and Q fluxons moves as a boson (fermion) if Q is odd (even). The quantum Hall effect can be interpreted as a manifestation of the condensation of the c-bosons. The plateau in the Hall resistivity with zero resistance is viewed as the Meissner effect. [Preview Abstract] |
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L1.00013: Inference of Schrodinger Equation from Classical Wave Mechanics[1] P-I. Johansson, J.X. Zheng-Johansson A localized oscillatory point charge $q$ generates in a one- dimensional box electromagnetic waves which for potential field $V=0$ may be generally described by monochromatic plane waves $\{ \varphi_i=C_K e^{i (KX-\Omega T + \alpha_i)} \}$ of angular frequency $\Omega$, wavevector $K=\Omega/c$, and initial phases $\{\alpha_i\}$, traveling at the velocity of light $c$. $q$ and $\{\varphi_i\}$ as a whole is here taken as a particle, which total energy ${\sf E}$ and mass $M$ are given by the basic equations ${\sf E} =\hbar \Omega= M c^2$, $2\pi\hbar$ being Planck constant. (For example, $q=-e$ amd $\hbar\Omega =511$ keV give an electron.) $\{\varphi_i\}$ as incident and reflected and those from the charge as reflected in the box superimpose into a total wave $\psi=\sum \varphi_i$ that, as with $\varphi_i$, obeys the classical wave equation (CWE): $c^2 \frac{d^2 \psi}{d X^2}= \frac{d^2\psi}{d T^2}$. If now the particle is traveling at velocity $v$, then $\{\varphi_i'\}$ are Doppler effected and form a total wave $\psi'={\mit \Phi} {\mit \Psi}$, with ${\mit \Psi}= C \sin (K_d X)e^{i \Omega_d T}$ enveloping a beat wave and identifiable as de Broglie wave of angular frequency $\Omega_d= \Omega (v/c)^2$, and ${\mit \Phi}$ being an undisplaced monochromatic wave. Using $\psi'$ in CWE (see [1]2004b for incorporation of $V\ne 0$), gives upon decomposition a separate equation describing the particle dynamics, $[-\frac{ \hbar^2 }{2 M } \frac{\partial ^2} {\partial X ^2}+V]{\mit \Psi}(X,T) =i\hbar\frac{\partial {\mit \Psi} (X,T) }{\partial T}$, which is equivalent to Schr\"odinger's equation. \quad [1] J. X. Zheng-Johansson and P-I. Johansson, arXiv:Physics/0411134 (2004a); "Unification of Classical, Quantum and Relativistic Mechanics and of the Four Forces", (Nova Science, 2004b). [Preview Abstract] |
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L1.00014: E6 Strings as World Lines Frank Smith E6 has spinor fermion generators for string theory with fermions but no 1-1 boson-fermion supersymmetry. Graded structure E6=g(-2)+g(-1)+g(0)+g(1)+g(2)gives a physically realistic representation of 26 dimensions of string theory with strings interpreted as world-lines. Physical interpretation allows calculations including: WMAP ratio 75.3:20.2:4.5; electromagnetic fine structure constant 1/137.03608; Gfermi 0.0000102; color force strength 0.6286 at 0.245 GeV (Nonperturbative QCD etc give color force strength 0.123 at 91 GeV); and particle masses, neutron-proton and UCC-DCC baryon mass differences, and neutrino mixing and K-M paramenters. See CERN CDS preprint EXT-2004-031 and CERN CDS preprint EXT-2003-087 and http://www.valdostamuseum.org/hamsmith/coscongraviton.html andhttp://www.valdostamuseum.org/hamsmith/snucalc.html{\#}asno . [Preview Abstract] |
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L1.00015: Debunking Non-Locality Causality N. Glenn Gratke Experiments purporting to confirm Non-Local Quantum Casuality are flawed in their interpretation. Reasserting Local Causality now helps to suggest a solution for the Unified Field Theory. [Preview Abstract] |
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L1.00016: TESTS OF PHYSICS LAWS
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L1.00017: On a New Theory of Physical Vacuum Temur Z. Kalanov A new theory of physical vacuum is proposed. This theory is based on the principle of unity of formal logic and dialectics. It is shown that physical vacuum does not represent system of material objects, not consist of particles, fields, bodies and is neither a particle, nor a field, nor a body. Therefore, vacuum has no properties (for example, energy, size) and, hence, does not interact with the objects of Nature. It means that both measure of vacuum energy and measure of vacuum information are equal to zero. Physical vacuum is matter in the state of absolute zero of energy and information. Thus, the new theory represents the philosophical solution of the problem of physical vacuum. This philosophical solution is the unique-permissible, rigorous, complete, general theoretical proof of existence of physical vacuum. [Preview Abstract] |
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L1.00018: Absolute and relative descriptions of an expanding space-time metric John Kulick The following is a transformation of a set of field equations describing the expansion of space-time from an ``absolute'' to a relative frame of reference. John Masreliez Ph.D. has had published a geometric description of a scalar expansion of space-time based upon relativistic measures and principles. A physicist named John Hunter has also developed a similar set of equations. The forms of the equations based upon an ``absolute'' reference frame initially do not appear to be the same but a transformation of the reference frames used shows that the equations are locally identical. There are a few fundamental differences. [Preview Abstract] |
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L1.00019: On the Correct Theoretical Analysis of the Foundations of Quantum Mechanics Temur Z. Kalanov The correct critical analysis of the generally accepted foundations of quantum mechanics is proposed [1]. The purpose of the analysis is to prove that the foundations include logical errors. The principle of the unity of formal logic and dialectics is a methodological basis of the analysis. The result is as follows: (a) the generally accepted foundations (i.e., the interpretation of the experimental data on diffraction of quantum particles; the conception of wave-corpuscle dualism; the probabilistic interpretation of the psi-function) are logical errors; (b) the pseudo-informational meaning is the true meaning of the psi-function. Conclusion is that quantum mechanics is not a physical, objective theory but a pseudo-informational one. Therefore, quantum mechanics should be replaced by a physical, objective quantum theory. Ref.: [1] T.Z. Kalanov. JUSPS, Vol. 16, No. 2 (2004), pp. 191--198, http://www.ultrascientist.org. [Preview Abstract] |
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L1.00020: Undecidability Theorem and Quantum Randomness Alexander A. Berezin As scientific folklore has it, Kurt Godel was once annoyed by question whether he sees any link between his Undecidability Theorem (UT) and Uncertainty Relationship. His reaction, however, may indicate that he probably felt that such a hidden link could indeed exist but he was unable clearly formulate it. Informational version of UT (G.J.Chaitin) states impossibility to rule out algorithmic compressibility of arbitrary digital string. Thus, (mathematical) randomness can only be disproven, not proven. Going from mathematical to physical (mainly quantum) randomness, we encounter seemingly random acts of radioactive decays of isotopes (such as C14), emission of excited atoms, tunneling effects, etc. However, our notion of quantum randomness (QR) may likely hit similarly formidable wall of physical version of UT leading to seemingly bizarre ideas such as Everett many world model (D.Deutsch) or backward causation (J.A.Wheeler). Resolution may potentially lie in admitting some form of Aristotelean final causation (AFC) as an ultimate foundational principle (G.W.Leibniz) connecting purely mathematical (Platonic) grounding aspects with it physically observable consequences, such as plethora of QR effects. Thus, what we interpret as QR may eventually be manifestation of AFC in which UT serves as delivery vehicle. Another example of UT/QR/AFC connection is question of identity (indistinguishability) of elementary particles (are all electrons exactly the same or just approximately so to a very high degree?). [Preview Abstract] |
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L1.00021: ACCELERATORS AND STORAGE RINGS
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L1.00022: Molecular arrangement of ethylene on Si(001) surface by CAICISS J.H. Seo, J.Y. Park, C.N. Whang, S.S. Kim, D.S. Choi, K.H. Chae C$_{2}$H$_{4}$ molecules have been non-dissociatively chemisorbed on Si(001)-(2$\times $1) surface at room temperature with an exposure of 100L, and C$_{2}$H$_{4}$ on Si(001) surface structure has been investigated by coaxial impact collision ion scattering spectroscopy (CAICISS). To determine the adsorption structure of the C$_{2}$H$_{4}$ molecules definitely, the computer simulation with the 2-D trajectory count method has been performed for the recently proposed most possible two single molecular adsorption configurations (di-$\sigma$ on-top and di-$\sigma$ end-bridge). The CAICISS spectra and simulation results show that the di-$\sigma$ on-top structure is better fit than the di- $\sigma$ end-bridge structure. It is found that the bond length of Si dimer separation on the Si(001) surface with the adsorption of C$_{2}$H$_{4}$ is $2.35 \pm 0.05 $ \AA. This implies that the bonding of Si dimers stays intact. It is also found that the bonding length of C--Si and C--C is $1.81 \pm 0.05$ \AA\ and $1.61 \pm 0.05$ \AA\, respectively. [Preview Abstract] |
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L1.00023: High Intensity Beam Extraction and Transport for SuSI -- the Superconducting Source for Ions at NSCL/MSU Nikolay Kazarinov, Peter Zavodszky The ion beam produced with an ECR ion source (ECRIS) with an extraction voltage of 30 kV may be additionally accelerated using a negative voltage of -30 kV applied to the third electrode of the accel-decel extraction system connected to the vacuum pipe of the beamline. The total kinetic energy of the beam may be increased up to 60 keV per unit charge. The influence of the space charge on the ion beam may be decreased more than two times and it is possible to remove the focusing elements from the analyzing part of the beamline with the simultaneous shortening of the distance between the ECRIS and the analyzing magnet. The voltage at the vacuum pipe of the beamline must be kept constant from ECRIS till the point of the full separation of the beam charge states placed near the focal plane of the analyzing magnet. At this point the vacuum pipe break is provided for increasing of the voltage up to ground value. The kinetic energy of the beam is decreasing down to about 30 keV per unit charge just after this point. For decreasing of the beam divergence the focusing solenoid is installed behind the break point. The simulation of the argon beam transportation in the proposed beam line is performed in this work. [Preview Abstract] |
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L1.00024: BEAM PHYSICS
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L1.00025: The Optical Assembly of Lens System in Microcolumn Won Jang, Jong Park, Ho Kim The resolution and performance of micro-column is determined by factors of optical aberration, which are dependent of the size, the roundness of lens aperture, and the precise alignment. The micro-column is composed of deflector, source lenses and Einzel lenses with the whole length less than 10mm. The optical aberrations of micro-column are reduced owing to the considerable reduction of its dimension compared with that of conventional electron column. A precise circular aperture was pierced on a 3$\mu $m thin silicon membrane by laser machining. The range of the aperture diameter of electron lenses usually ranges from 10 to 200$\mu $m, and the spacing between electrodes is from 100$\mu $m to several hundreds of $\mu $m. Laser diffraction pattern observed through the assembled lens system, and the distortion of the diffraction pattern can be easily recognized. An Airy circular diffraction was observed and monitored for the clear pattern.. [Preview Abstract] |
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L1.00026: PLASMA PHYSICS
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L1.00027: Measurements of the two-point correlation function for plasma ions Fred Skiff, Ahmed Diallo, Ilker Uzun We present extensive measurements of the two-point correlation function for plasma ions in the presence of drift-wave instability in a uniformly magnetized plasma cylinder. By means of laser-induced fluorescence we resolve the measurements in the component of ion velocity parallel to the magnetic field in addition to the spatial coordinates of the two points. Thus we measure {f(x,y,z1,vz)*f(x,y,z2,vz)} where z is the direction parallel to the magnetic field. In addition to the contribution of the drift wave modes, we observe a kinetic component that has short wavelengths parallel to the magnetic field. The observed wavelengths are such that the kinetic component of the fluctuations has a phase velocity comparable to the ion particle velocities and is found to vary with ion velocity (vz). The kinetic component is also highly asymmetric in propagation direction and shows evidence of nonlinearity (high frequency-harmonic content). At present, there is no adequate explanation for the kinetic component of the fluctuations. We consider the possibility that the drift-waves are coupling energy to the kinetic component despite the fact that the wavelengths differ by two orders of magnitude. [Preview Abstract] |
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L1.00028: \textbf{Laboratory simulation of magnetized astrophysical jets} R. Presura, L.F. Wanex, V.I. Sotnikov, A. Esaulov Open questions regarding astrophysical jets nclude the mechanisms responsible for their collimation during propagation over distances at least 10 times larger than their diameter. Several laboratory experiments designed to address the role of stability and radiative cooling upon the collimation of magnetized jets will be presented. They are based on scaling and realistic facilities. Scaling issues will be presented. The plasma jets will be created by laser ablation ($I\le $1PW/cm$^{2})$, and fields (\textbf{\textit{B}}$\le $0.5MG, \textbf{\textit{E}}$\le $200kV/cm) will be produced independently by a fast pulsed power generator. This combination allows for the generation of magnetized jets and, in particular, current carrying jets. Depending on the elemental composition, the jets can be made radiative or not. An addition external magnetic field can be used to produce jet rotation. Experimental results will be used to verify predictions of linear MHD theory and MHD modeling. In particular, the effects of sheared axial flow, sheared azimuthal flow, and axial magnetic field upon the MHD stability of current carrying jets will be investigated. Work supported by DOE/NNSA under UNR grant DE-FC52-01NV14050. [Preview Abstract] |
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L1.00029: Initial Results of the Madison Dynamo Experiment Erik Spence, Cary Forest, Craig Jacobson, Roch Kendrick, Mark Nornberg, Rob O'Connell The Madison Dynamo Experiment is a 1 m diameter spherical vessel filled with flowing liquid sodium used to study magnetic field generation and magnetohydrodynamic (MHD) turbulence. External magnetic fields are used to probe the electromagnetic properties of flowing liquid sodium. A square-wave external magnetic field is applied to the sphere and the response magnetic field, generated by the fluid, is measured by an array of external Hall probes. The fluid's response field is used to invert the velocity field of the fluid, using the multiple frequencies of the applied field contained within the square wave. The inverted velocity field is compared to the velocity field directly measured in a scale water model of the experiment. Characteristics of the MHD turbulence are presented, and the role of turbulence in the fluid's response field is discussed. [Preview Abstract] |
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L1.00030: Evidence of an Influx of Interstellar Plasma from Archaic Z-Pinch Recordings A. L. Peratt, M. A. van der Sluijs, D. A. Scott Many dozens of categories of instabilities associated with sub-gigaampere Z-pinches from digitally logged archaic petroglyphs have been identified \footnote[1]{ A. L. Peratt, `Characteristics for the occurrence of a high-current Z-pinch aurora as recorded in antiquity', Trans. Plasma Sci. Vol. 31, N. 6, 2003.} as might occur in an intense aurora\footnote[2]{ T. Gold, `Large solar outburst in the past,' Pontificiae Academiae Scientiarvm Scripta Varia, Vol. 25, pp. 159-174, The Vatican, 1962.}or the influx of interstellar plasma\footnote[3]{ Frisch, P. C.; `Morphology and Ionization of the Interstellar Cloud Surrounding the Solar System,' Science, 265:1423, 1994.}. The data included fields of view (FOV's) for sites in Italy, the western United States, northern South America, and the Middle East. In all cases, the petroglyphs have a magnetic south FOV component. The southern horizon inclination angles of the carvings were nearly zero degrees at 50$^o$ latitude increasing to 23.5 degrees at 36$^o$ latitude. This suggests the presence of an intense prehistoric southerly influx. We present digital elevation data where the southern-most petroglyph locations silhouette profiles of mountains, often many kilometers to the south. [Preview Abstract] |
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L1.00031: Chapman-Ferraro-like magnetopause in the laboratory R. Presura, V.V. Ivanov, A. Esaulov, Y. Sentoku, V.I. Sotnikov, J. Fuchs, N. Le Galloudec, P.J. Laca, A.L. Astanovitskiy, B. Le Galloudec, C. Plechaty, B. Goettler, R.J. Hall, A. Clinton, T. Cowan, W. Horton, C. Chiu, T. Ditmire A laboratory simulation of the interaction of the solar wind with the earth's magnetosphere is presented. The plasma wind was created ablating a solid CH$_{2}$ target with up to 0.1PW/cm$^{2}$ pulses of the ``Tomcat'' Nd:glass laser. Azimuthal magnetic fields with strength up to 20 T were generated by high current discharges of the ``Zebra'' pulsed-power generator. A dynamic boundary layer with steep density gradient forms at the plasma-field interface. It acts as a piston and has the potential of launching collisionless shocks into the continuing plasma flow from the laser focus region. Features of the plasma expansion in the external magnetic field are well reproduced by 3D-ideal-MHD modeling. A fully particle approach is needed to understand the plasma dynamics, particularly the plasma expansion beyond the stopping point predicted by ideal MHD. Work supported by DOE/NNSA under UNR grant DE-FC52-01NV14050. [Preview Abstract] |
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L1.00032: Magnetic Reconnection and Associated Transport of Plasma Thermal Energy V. Roytershteyn, B. Coppi, C. Yarim The high-temperature theory of the collisional drift-tearing mode [1] that associates a process of magnetic reconnection with the thermal energy transport is presented. In the regimes relevant to present day experiments the longitudinal electron thermal conductivity plays a key role. The novel analysis that has been developed [2] shows that while the onset of the mode alters the magnetic field topology on a macroscopic scale, the associated fluid velocities are basically localized in the region where magnetic reconnection takes place and the effects of finite electron conductivity are important. The characteristics of the mode and of the reconnection region are shown to differ significantly from the ones described in the original work [1] where regimes with relatively high collisionality were considered. The limitations on the linear mode amplitude necessary for the validity of the linearized approximation are identified and a highly simplified non-linear model equation to describe the mode evolution is considered.\par \noindent [1] B. Coppi, \textit{Phys. Fluids}, \textbf{8}, 2273 (1965). \par \noindent [2] B. Coppi, V. Roytershteyn and C. Yarim, Paper IAEA-CN-116/TH/P2-29, I.A.E.A. Fusion Conference 2004 [Preview Abstract] |
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L1.00033: Advances in the Accretion Theory of the Spontaneous Rotation Phenomenon M. Lontano, B. Coppi The accretion theory [1] of the spontaneous rotation phenomenon has found further confirmation in the series of experiments carried out by the Alcator C-Mod [2] and DIII-D machines [3]. This theory was the first based on having the source of angular momentum near the edge of the plasma column so that a change of the edge configuration can effect the velocity of rotation. This has been verified by the Alcator C-Mod experiments with lower and upper null configurations exhibiting drastically different toroidal velocities. The intrinsic coupling between spontaneous rotation and thermal energy transport involved in the accretion theory is consistent with the observed relationship [2] between the change of rotation velocity from the L-confinement regime to the H-confinement regime and the scaling of the threshold to attain the H-regime. The DIII-D experiments involving electron cyclotron heating have confirmed the existence of spontaneous rotation and shown the toroidal velocity to be proportional to $(T_e/T_i)W_{th}$ where $W_{th}$ is the total thermal energy of the plasma column and the $(T_e/T_i)$ ratio is consistent with the excitation of the ITG modes that can carry angular momentum toward the center of the plasma column [1].\par \noindent [1] B. Coppi, {\it Nucl. Fusion} {\bf 42}, 1 (2002). \par \noindent [2] J. Rice et al, 20th IAEA Fus. En. Conf CN-116/EX/6- 4Ra. \par \noindent [3] J.S. deGrassie et al, 20th IAEA Fus. En. Conf CN- 116/EX/6-4Rb. [Preview Abstract] |
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L1.00034: Advances in the Ignitor Program F. Bombarda, B. Coppi There have been significant advances both in finalizing the design of the Ignitor machine and in understanding the plasma physics regimes that the experiments by Ignitor are expected to cover. Among the former, there is a new configuration of the plasma chamber and a solution for the first wall (Molybdenum tiles and tile carriers), the optimization and simplification of the entire poloidal field system, the successful test of key components of a 4 km/s pellet injector, the completed construction of the second generation prototypes of the toroidal magnet plates, the definition of the power supply system. For the physics, the achievement by the Alcator C- --Mod machine of 2 MA plasmas at 8 T supports the expectation that Ignitor will attain 11 MA with consistent safety factors. A realistic form of control of the plasma temperature in view of the “thermonuclear instability” onset as ignition is approached, has been simulated by the JETTO 1+1/2 D transport code and consists in coordinating the value of the plasma density that influences strongly the plasma resistivity, and the ICRH system that is employed to keep the plasma slightly “undercritical” but yet with high values of Q. A study of Ignitor plasmas in a variety of regimes other than the reference ignition scenario has been carried out, showing that even without tritium and with Ohmic heating alone novel physical regimes can be attained, largely exceeding the results of present day devices. [Preview Abstract] |
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L1.00035: Non-Neutral Drift Resonance in Magnetrons D.J. Kaup We study the features of the RF fields in a magnetron, when the RF amplitude has saturated, in the nonrelativistic, electrostatic limit. In this saturated stage, the linear RF equations can be reduced to a fifth-order set of ordinary differential equations. Two modes of which are fast cyclotron modes, one mode is a fast drift wave, and the other two modes are the usual, well-known, slow magnetron modes. Here, we will study the interaction between the fast drift mode (diocotron mode) and the slow magnetron modes, at the diocotron resonance. We will also show that the fast cyclotron modes can be ignored at this resonance, and thereby can reduce the system to a third- order set of ordinary differential equations. Using multiscale techniques, we will then obtain solutions for the inner and the outer regions at the diocotron resonance, and thereby obtain the conversion and transmission rates between these three modes at the diocotron resonance. [Preview Abstract] |
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L1.00036: PIC code simulation of electromagnetic braking of an antiproton beam using a slow wave structure Douglas Young There has been a great deal of recent interest in the trapping of antiprotons in magnetic traps for a variety of purposes. One of the problems with constructing these traps is the high energy the antiprotons have after their creation. The standard method for reducing the energy of the antiprotons is to pass a beam through moderators to slow the antiprotons. While this does slow them, it also destroys many of the antiprotons in the process. This poster will examine the use of a slow wave structure as a braking mechanism for an antiproton beam. A slow wave structure is essentially a rippled waveguide. By injecting an electron beam of moderate energy into a rippled waveguide, energy from the beam is converted into electromagnetic energy, typically into microwaves. This poster will present results of computer particle-in-cell simulations using the computer code OOPIC to determine the efficacy of using a slow wave structure as a braking mechanism for an antiproton beam. [Preview Abstract] |
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L1.00037: Center of Universe, Big Bang's Downfall, and the Great White Throne Robert Gentry In Feb. 2001 Paul Ginsparg and his LANL associates censored the release of my ten-paper disproof of big bang cosmology and discovery of a new cosmic model, GENESIS, from Arxiv. Since then Ginsparg and his Cornell associates have continued to do the same (see www.orionfdn.org). I then posted some results on CERN before it too began to exclude such persons as myself. On it I showed the correct calculation of big bang's spacetime expansion prediction of the CBR temperature is not the experimentally obtained 2.73K, but instead is less that 0.0001K (CERN EXT-2003- 021). This contradiction invalidates big bang's F-L spacetime postulate, its expansion redshifts, its explanation of the Hubble relation and CBR temperature. Big bang's downfall came about because its previously untested postulates have been shown to be vacuous. To replace it I have discovered a new Cosmic Center Universe model that reproduces eight of big bang's most important predictions (see CERN EXT-2003-022). This Universal nearby Center is identified with God's dwelling place, the Great White Throne described in Revelation 20 and 22. These results prove the heavens declare the glory of God, not the big bang. [Preview Abstract] |
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