Session D1: Inflation

Session D2: Bethe and Bonner Prizes

Hans A. Bethe Prize Talk: LUNA: a Laboratory Underground for Nuclear Astrophysics

It is in the nature of astrophysics that many of the processes and objects one tries to understand are physically inaccessible. Thus, it is important that those aspects that can be studied in the laboratory be rather well understood. One such aspect are the nuclear fusion reactions, which are at the heart of nuclear astrophysics: they influence sensitively the nucleosynthesis of the elements in the earliest stages of the universe and in all the objects formed thereafter, and control the associated energy generation, neutrino luminosity, and evolution of stars. I review a new experimental approach for the study of nuclear fusion reactions based on an underground accelerator laboratory, named LUNA.   

Tom W. Bonner Prize in Nuclear Physics Talk: Nuclear Forces and the Universe

A major goal in nuclear physics is to understand how nuclear binding, structure, and reactions can be obtained from the underlying interactions between individual nucleons. Significant progress in formulating realistic Hamiltonian descriptions of nuclear interactions, and in accurately solving the many-nucleon Schr\"odinger equation, has been made over the past two decades. This includes the development of a number of two-nucleon ($N\!N$) potentials that accurately reproduce elastic $N\!N$ scattering data and deuteron properties, as well as consistent three-nucleon ($3N$) potentials and multi-nucleon charge and current operators. Using sophisticated many-body theory, such as the quantum Monte Carlo (QMC) methods described in the following talk, we find that realistic Hamiltonians can indeed reproduce the structure and reactions of light nuclei extremely well. The interactions that reproduce $N\!N$ scattering are quite complicated, including central, spin, isospin, tensor, and spin-orbit terms. One-pion exchange between nucleons and iterated two-pion exchange with intermediate-$\Delta$ excitations, which contributes to both $N\!N$ and $3N$ potentials, are crucial components. Using fully realistic potentials and progressively simplified versions in our QMC calculations, we have studied what elements of these forces are necessary to get some key features of nuclear structure, like the absence of stable five- and eight-body nuclei. This absence is important for primordial nucleosynthesis and the long-lived stability of stars like our sun. We can also study the sensitivity of nuclear binding to possible variations in hadronic masses. Thus we can address several questions about how ``fine-tuned'' our universe is.   

Tom W. Bonner Prize in Nuclear Physics Talk: Finding Real Nuclei in Imaginary Time

Ab initio calculations of nuclei treat a nucleus as a system of $A$ nucleons interacting by realistic two- ($N\!N$) and three-nucleon ($N\!N\!N$) forces. Variational Monte Carlo (VMC) followed by Green's function Monte Carlo (GFMC) is a very successful ab initio method for light nuclei. The VMC gives an upper bound to the true energy of a nucleus for a given Hamiltonian; the closeness of the upper bound to the exact solution of the Schr\"odinger equation depends on the physical insight built into the trial wave function, $\Psi_T$, that is used. GFMC starts with a $\Psi_T$ and, by propagation in imaginary time, allows the exact lowest eigenenergy for a given set of quantum numbers to be computed. The first VMC calculations of nuclei were published in 1981 by Lomnitz-Adler, Pandharipande, and Smith. They were for $^3$H and $^4$He using the Reid $N\!N$ potential. Six years later, Carlson published the first GFMC calculations of nuclei, again for $^3$H and $^4$He, but using a slightly-simplified $N\!N$ potential; in the following year he used the full Reid V8 potential. Pudliner, Pandharipande, Carlson, and Wiringa published GFMC calculations of $A$=6 nuclei in 1995, using the Argonne V18 $N\!N$ potential and the Urbana IX $N\!N\!N$ potential. Since then there has been steady progress in applying GFMC to larger nuclei. This has been from both increasing computer power and new or improved algorithms. The largest computers are increasingly difficult to use efficiently, but, as a result of a SciDAC collaboration, we now get excellent scalability up to 131,000 cores on Argonne's IBM Blue Gene/P. In addition we have found that the GFMC can be used for multiple states with the same quantum numbers. With the Argonne V18 and Illinois $N\!N\!N$ potentials, we obtain an excellent description of the properties of nuclei up to $A = 12$. I will describe these methods, present recent advances in using the largest computers, and some recent results.   

Session D3: Mentoring Perspectives of Mentor and Mentee

``Crossing the Bridge'' One Student's Journey Through the Fisk-Vanderbilt Masters to Ph.D. Program

Matriculating through graduate school is a process that molds a student to be successful both academically and professionally. Selecting the perfect mentor to aid in that process can be a daunting task. Moreover, looking to one mentor to meet every academic or professional need may not be fitting for every student. It has been my experience that it is difficult to look to one mentor for every need or inquiry I face. As a result I have built a network of mentors each with a specific purpose and area of expertise that will assist in achieving my goals as a graduate student and a scientist. This talk will discuss one student's quest for ``the perfect mentor'' while matriculating through the Fisk-Vanderbilt Masters-to Ph.D. program.   

Mentoring Masters-to-PhD Students: Reflections of the Fisk-Vanderbilt Masters to PhD Bridge Program

As a research advisor and mentor to students who are enrolled in the Fisk-Vanderbilt Bridge program, I will discuss the development of the program and some of the unique challenges that face students who are transitioning from the Masters program into the PhD program. These comments will include the mentorship that has been cultivated and continues to develop among Fisk Masters students and their potential Vanderbilt PhD advisors, the partnership among Fisk and Vanderbilt faculty to ensure as seamless a transition as possible for our students, and other related topics.   

Systemic Mentoring for Competitiveness: The Model of the Timbuktu Academy

The Timbuktu Academy is a comprehensive, systemic mentoring program at Southern University and A{\&}M College in Baton Rouge (SUBR), Louisiana. We define systemic mentoring as one that is woven into the core functions of an organization. For most universities, those functions include instruction, research, and service. While the Academy has programs for pre-college and graduate students, its Ten-Strand Systemic Mentoring Model was specifically tailored to undergraduate education. We discuss basic considerations that led to the paradigm, programs, activities, and results of the Timbuktu Academy. The proper implementation of the Ten-Strand Systemic Mentoring Model couples teaching and superior learning, on the one hand, and integrates research and education, on the other hand. For undergraduate education, key strands include support (financially or otherwise), scientific advisement, research participation (academic year or summer), immersion in a professional culture, monitoring, and guidance to graduate school. From the summer of 1994 to 2009, the Academy has engaged 2,093 pre-college scholars in its summer programs. To date, the Academy has assisted in the production of one hundred seventy (170) minority undergraduate scholars who have earned a Bachelor of Science degree. Seventy (70) of 83 physics graduates, twenty (20) of 29 chemistry graduates, and twenty-two (22) of 49 engineering graduates have earned graduate degrees or are successfully enrolled in graduate school, with emphasis on the pursuit of the Ph.D. For the above model and results, the Timbuktu Academy received the 2002 U.S. Presidential Award for Excellence in Science, Mathematics, and Engineering Mentoring. Its director was among the first individual recipients of this award in 1996. The handouts accompanying this presentation are intended to facilitate the adaptive replication of the Timbuktu Academy by individuals, departments, colleges and universities, and other organizations.   

Session D4: Probing Strong-Field Gravity with Observations of the Galactic Center Black Hole

Probing strong-field gravity at the galactic center using stellar motions

The center of our galaxy contains the nearest supermassive black hole, with a mass four million times that of the Sun. The black hole's location and mass have been accurately determined by tracing the motions of a handful of bright young stars that move in tight orbits about the Galactic center, some with periods as short as 15 years. Until now, the measured orbits have been found to be consistent with Keplerian ellipses about a Newtonian point mass. But the stellar orbits potentially contain much more information: about the distributed mass in the inner parsec (consisting of faint stars, dark stellar remnants, and possibly particle dark matter); and also about the non-Newtonian contributions to the gravitational potential from the supermassive black hole. For stars nearer than about one milli-parsec from the singularity, frame-dragging torques should induce precession of orbital planes at a rate that is potentially observable after a few years' monitoring using the next generation of optical astrometric instruments, allowing a direct determination of the black hole's spin. Even more challenging would be a test of 'no hair' theorems by comparing the frame-dragging precession with that induced by the black hole's quadrupole moment. Results of detailed numerical simulations of the nuclear star cluster that include relativistic terms will be presented, which demonstrate the feasibility of testing theories of gravity using stellar orbits, given the inevitable noise from star-star perturbations and perturbations due to the unseen stellar remnants.   

Observing an Event Horizon: (sub)mm Wavelength VLBI of SgrA*

A long--standing goal in astrophysics is to directly observe the immediate environment of a black hole with angular resolution comparable to the event horizon. Realizing this goal would open a new window on the study of General Relativity in the strong field regime, accretion and outflow processes at the edge of a black hole, the existence of event horizons, and fundamental black hole physics (e.g., spin). Steady long--term progress on improving the capability of Very Long Baseline Interferometry (VLBI) at short wavelengths has now made it extremely likely that this goal will be achieved within the next decade. The most compelling evidence for this is the recent observation, using 1.3mm wavelength VLBI, of Schwarzschild radius scale structure in SgrA*, the compact source of radio, submm, NIR and xrays at the center of the Milky Way. There is now very strong evidence that SgrA* marks the position of a $\sim4$ million solar mass black hole, which, due to its proximity and estimated mass, presents us with the largest apparent event horizon size of any black hole candidate in the Universe. By extending the observing wavelength of VLBI to the sub--mm bands, we will achieve angular resolution sufficient to detect strong field GR effects on the appearance of the plasma surrounding the black hole. Short wavelength VLBI can also be used to directly detect signatures of matter spiraling into the black hole with the potential to estimate the periods of orbits close to the event horizon. I will discuss what current VLBI observations of SgrA* tell us about this closest super--massive black hole, describe the exciting potential of future work, and outline plans to assemble a Global submm-VLBI ``Event Horizon Telescope".   

Nature of the black hole in the center of the Milky Way

Recently, mm-VBLI observations capable of resolving sub-horizon structure in the emission from Sgr A*, the supermassive black hole at the center of the Milky Way, have become possible. These promise to open a new window upon the physics of black hole accretion, jet formation and gravity itself. Already, when combined with existing observations at other wavelengths, it is possible to place extraordinary constraints upon the existence of a horizon in Sgr A*, subject only to the assumption that gravity is a metric theory admitting stationary solutions. I will describe what we expect to see, how this will inform our understanding of gas dynamics near black holes, and what we've learned about the fundamental nature Sgr A* already.   

Session D5: Nonproliferation

Leo Szilard Lectureship Award Talk: Controlling and eliminating nuclear-weapon materials

Fissile material -- in practice plutonium and highly enriched uranium (HEU) -- is the essential ingredient in nuclear weapons. Controlling and eliminating fissile material and the means of its production is therefore the common denominator for nuclear disarmament, nuclear non-proliferation and the prevention of nuclear terrorism. From a fundamentalist anti-nuclear-weapon perspective, the less fissile material there is and the fewer locations where it can be found, the safer a world we will have. A comprehensive fissile-material policy therefore would have the following elements: \begin{enumerate} \item Consolidation of all nuclear-weapon-usable materials at a minimum number of high-security sites; \item A verified ban on the production of HEU and plutonium for weapons; \item Minimization of non-weapon uses of HEU and plutonium; and \item Elimination of all excess stocks of plutonium and HEU. \end{enumerate} There is activity on all these fronts but it is not comprehensive and not all aspects are being pursued vigorously or competently. It is therefore worthwhile to review the situation.   

U.S.-Russian cooperation in nuclear disarmament and nonproliferation

The United States and Russia, the two largest nuclear powers, have a special obligation to provide leadership in nuclear disarmament and in strengthening the nuclear non-proliferation regime. In the past year the two countries made an effort to restart the arms control process by concluding a new treaty that would bring their legal disarmament obligations in line with the realities of their post-cold war relationships. The process of negotiating deeper nuclear reductions in the new environment turned out to be rather difficult, since the approaches that the countries used in the past are not well suited to dealing with issues like conversion of strategic nuclear delivery systems to conventional missions, tactical nuclear weapons, or dismantlement of nuclear warheads. This presentation considers the recent progress in U.S.-Russian arms control process and outlines the key issues at the negotiations. It also considers prospects for further progress in bilateral nuclear disarmament and issues that will be encountered at later stages of the process. The author argues that success of the arms reductions will depend on whether the United States and Russia will be able to build an institutional framework for cooperation on a range of issues - from traditional arms control to securing nuclear materials and from missile defense to strengthening the international nuclear safeguards.   

In search of plutonium: A nonproliferation journey

In February 1992, I landed in the formerly secret city of Sarov, the Russian Los Alamos, followed a few days later by a visit to Snezhinsk, their Livermore. The briefings we received of the Russian nuclear weapons program and tours of their plutonium, reactor, explosives, and laser facilities were mind boggling considering the Soviet Union was dissolved only two months earlier. This visit began a 17-year, 41 journey relationship with the Russian nuclear complex dedicated to working with them in partnership to protect and safeguard their weapons and fissile materials, while addressing the plight of their scientists and engineers. In the process, we solved a forty-year disagreement about the plutonium-gallium phase diagram and began a series of fundamental plutonium science workshops that are now in their tenth year. At the Yonbyon reprocessing facility in January 2004, my North Korean hosts had hoped to convince me that they have a nuclear deterrent. When I expressed skepticism, they asked if I wanted to see their ``product.'' I asked if they meant the plutonium; they replied, ``Well, yes.'' Thus, I wound up holding 200 grams of North Korean plutonium (in a sealed glass jar) to make sure it was heavy and warm. So began the first of my six journeys to North Korea to provide technical input to the continuing North Korean nuclear puzzle. In Trombay and Kalpakkam a few years later I visited the Indian nuclear research centers to try to understand how India's ambitious plans for nuclear power expansion can be accomplished safely and securely. I will describe these and other attempts to deal with the nonproliferation legacy of the cold war and the new challenges ahead.   

Session D6: Particle Beams and Accelerators in Energy Research and Applications

Increasing the Acceptance of Spent Nuclear Fuel Disposal by the Transmutation of Minor Actinides Using an Accelerator

The main challenge in nuclear fuel cycle closure is the reduction of the potential radiotoxicity of spent LWR nuclear fuel, or the length of time in which that potential hazard exists. Partitioning and accelerator-based transmutation in combination with geological disposal can lead to an acceptable societal solution for the nuclear spent fuel management problem. Nuclear fuel seems ideally suited for recycling. Only a small fraction of the available energy in the fuel is extracted in a single pass and the problem isotopes, consisting of the transuranic elements plutonium, neptunium, americium, curium and the long-lived fission products iodine and technetium, could be burned in fast-neutron spectrum reactors or sub-critical accelerator driven transmuters. Most of the remaining wastes have half-lives of a few hundred years and can be safely stored in man-made containment structures (casks or glass). The very small amount of remaining long-lived waste could be safely stored in a small geologic repository. The problem for the next 100 years is that a sufficient number of fast reactors are unlikely to be built by industry to burn its own waste and the waste from existing and new light water reactors (LWRs). So an interim solution is required to transition to a fast reactor economy. The goals of accelerator transmutation are some or all of the following: 1) to significantly reduce the impacts due to the minor actinides on the packing density and long-term radiotoxicity in the repository design, 2) preserve/use the energy-rich component of used nuclear fuel, and 3) reduce proliferation risk. Accelerator-based transmutation could lead to a greater percentage of our power coming from greenhouse-gas emission-free nuclear power and provide a long-term strategy enabling the continuation and growth of nuclear power in the U.S.   

Plasma Heating and Current Drive for Fusion Reactors

ITER (in Latin ``the way'') is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier one and thus release energy. In the fusion process two isotopes of hydrogen - deuterium and tritium - fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q $\geq$ 10 (input power 50 MW / output power 500 MW). In a Tokamak the definition of the functionalities and requirements for the Plasma Heating and Current Drive are relevant in the determination of the overall plant efficiency, the operation cost of the plant and the plant availability. This paper summarise these functionalities and requirements in perspective of the systems under construction in ITER. It discusses the further steps necessary to meet those requirements. Approximately one half of the total heating will be provided by two Neutral Beam injection systems at with energy of 1 MeV and a beam power of 16 MW into the plasma. For ITER specific test facility is being build in order to develop and test the Neutral Beam injectors. Remote handling maintenance scheme for the NB systems, critical during the nuclear phase of the project, will be developed. In addition the paper will give an overview over the general status of ITER.   

Light Driven Energy Research at LCLS: Planned Pump-Probe X-ray Spectroscopy Studies on Photosynthetic Water Splitting

Arguably the most important chemical reaction on earth is the photosynthetic splitting of water to molecular oxygen by the Mn-containing oxygen-evolving complex (Mn-OEC) in the protein known as photosystem II (PSII). It is this reaction which has, over the course of some 3.8 billion years, gradually filled our atmosphere with O$_2$ and consequently enabled and sustained the evolution of complex aerobic life. Coupled to the reduction of carbon dioxide, biological photosynthesis contributes foodstuffs for nutrition while recycling CO$_2$ from the atmosphere and replacing it with O$_2$. By utilizing sunlight to power these energy-requiring reactions, photosynthesis also serves as a model for addressing societal energy needs as we enter an era of diminishing fossil hydrocarbon resources. Understanding, at the molecular level, the dynamics and mechanism of how nature has solved this problem is of fundamental importance and could be critical to aid in the design of manufactured devices to accomplish the conversion of sunlight into useful electrochemical energy and transportable fuel in the foreseeable future. In order to understand the photosynthetic splitting of water by the Mn-OEC we need to be able to follow the reaction in real time at an atomic level. A powerful probe to study the electronic and molecular structure of the Mn-OEC is x-ray spectroscopy. Here, in particular x-ray emission spectroscopy (XES) has two crucial qualities for LCLS based time-dependent pump-probe studies of the Mn-OEC: a) it directly probes the Mn oxidation state and ligation, b) it can be performed with wavelength dispersive optics to avoid the necessity of scanning in pump probe experiments. Recent results and the planned time dependent experiments at LCLS will be discussed.   

Session D7: Soft and Hard Interactions at RHIC

Measurements of High pT $\pi^0$ Azimuthal Anisotropy in Au+Au Collisions at $\sqrt{s_{NN}}$ = 200 GeV at PHENIX

The phenomena of jet suppression has been well established via separate measurements of the nuclear modification factor $R_{AA}$, azimuthal anisotropy and di-hadron correlations. The current challenge is to quantitatively understand the underlying suppression mechanism, as well as to understand the interplay between jet suppression, collective flow and coalescence as function $p_T$. Meeting this challenge requires new measurements which extend the current experimental $p_T$ reach and combine the constraining power of $R_{AA}$ and anisotropy. In a recent experimental run (Year-2007), the PHENIX experiment collected over 800 $\mu b^{-1}$ in integrated luminosity of Au+Au collisions. Augmented with newly installed high resolution reaction plane detectors, this wealth of high statistics data allows detailed measurements of $R_{AA}$ relative to the reaction plane. The results using $\pi^0$s will be presented and compared with various energy loss model calculations. We will also study the $v_2$ results in different $p_T$ regions, and compare them using reaction plane determined in various $\eta$ windows. The former can shed light on the interplay between jet suppression, collective flow and coalesces, the later can help us to quantify the non-flow effects due to jets.   

Effects of Fluctuations in the Fireball on Jet Quenching Observables at RHIC

In high energy nuclear collisions, jet energy loss is usually modeled with smooth, homogeneous backgrounds. We study the effect of realistic, inhomogeneous backgrounds by implementing Glauber profiles with fluctuations. We observe how the extraction of the energy loss parameter is affected by these fluctuations and we calculate their effect on observables like single hadron spectra, nuclear modification factor, azimuthal asymmetry, back-to-back correlations and triggered fragmentation functions.   

Inclusive Jet and Dijet Cross Section Measurements in Polarized Proton-Proton Collisions at 200 GeV at STAR

The STAR detector at the RHIC polarized proton-proton collider has full-azimuth calorimeter and tracking devices well suited for full jet reconstruction for the pseudorapidity range $|\eta| \le 1$. We report the status of the inclusive jet and dijet cross section measurements in proton collisions at 200 GeV. The jet cross sections are fundamental quantities to test the framework of the QCD factorization and perturbative QCD calculations. Dijet measurements provide additional sensitivity to parton kinematics. The jet cross sections are important steps to interpret jet spin asymmetries in polarized proton collisions that we measure to constrain the polarized gluon distribution of the proton in order to understand the spin structure of the proton.   

Determining sampled luminosity in proton-proton collisions at $\sqrt{s}= 500$~GeV at STAR using the vernier scan technique

The STAR experiment at RHIC serves as an excellent laboratory for studying spin in QCD. Comparing predicted and measured cross sections requires accurate measurements of the luminosity. At RHIC, the absolute luminosity of colliding beams is determined through a vernier scan, where trigger rates at STAR are recorded as a function of the impact parameter of RHIC's two proton beams. The details of this method as implemented at STAR will be presented. In particular, the status of the analysis of a 2009 $\sqrt{s}= 500$~GeV trigger based on the STAR barrel electromagnetic calorimeter will be shown.   

A new pixel sensor concept for Heavy Flavor Tracker in STAR at RHIC

A new pixel sensor concept is proposed and simulated to improve the performance of the Heavy Flavor Tracker in STAR at RHIC. The new sensor is a multi-wire chamber with silicon readout connected. The new sensor uses the standard CMOS technology to fabricate. It inherits merits from both multi-wire chamber and silicon active pixel sensor. The new sensor can have high position resolution and high signal to noise ratio. It also has high radiation tolerance by removing the sensor diode from silicon. The new sensor also can have fast and flexible on-chip readout.   

Study of mutual influence of jet and flow In heavy ion collisions using AMPT model

The two particle correlations in heavy ion collisions are often analyzed using a two source model: high energy jets that are produced during the early stages of the collision and the collective flow of the bulk medium which is a result of its (ideal) fluid like behavior and its initial geometrical anisotropy. Such analysis reveals striking features, such as suppression of away side jet and Mach-Cones. However, the two source model has the disagreeable assumption that the jet and flow are independent of each other, which casts doubts over the results obtained using this model. In order to get an understanding of jet-flow correlations and test the validity/failure of the two source model, we study simulations of Au-Au collisions at RHIC energies using the AMPT model. To isolate the effects of the jet, we simulate events with and without high $p_T$ jets and compare azimuthal distributions and $p_T$ spectrum of particles as well as the two particle correlations. We will discuss the effects of the Jet on the above mentioned observables and how the jet can both enhance and reduce the $V2$ depending on the $p_T$ of the observed particles and the embedded jet.   

RHIC Motivated Hydrodynamics from a Schwarzschild Black Hole

We discuss the derivation of dissipative Bjorken hydrodynamics from a Schwarzschild black hole in asymptotically AdS spacetime in the limit of large longitudinal proper time $\tau$. Using an appropriate slicing near the boundary, we calculate the Schwarzschild metric to next-to-next-to-leading order in the large $\tau$ expansion as well as the dual stress-energy tensor on the boundary via holographic renormalization. At next-to-next-to-leading order, it is necessary to perturb the Schwarzschild metric in order to maintain boost invariance. The perturbation has a power law time dependence and leads to the same value of the ratio of viscosity to entropy density, $1/(4\pi)$, as in the case of sinusoidal perturbations. Our results are in agreement with known time-dependent asymptotic solutions of the Einstein equations in five dimensions.   

Session D8: Mini-Symposium on Physics with an Electron-Nucleus Collider

Nuclear Physics with an Electron-Ion Collider

An overview is given of the science program with an Electron--Ion Collider (EIC) with CM energies in the range $10^3$--$10^4 \, {\rm GeV}^2$, as envisaged by the U.S.\ and international nuclear physics community and endorsed in the 2007 NSAC Long--Range Plan. It includes precision studies of nucleon structure in QCD (gluon spin, quark flavor decomposition, gluon and sea quark spatial distributions or GPDs, parton orbital motion or TMDs), the fundamental quark/gluon structure of nuclei (nuclear gluons and EMC effect, nuclear quark/gluon radii from coherent scattering, hadronization in the nuclear medium), and the physics of high gluon densities at small x (saturation, Color Glass Condensate). Particular emphasis will be put on demonstrating the unique potential of an EIC for addressing these objectives, and discussing the proposed measurements in the context of the programs at other exisiting and planned facilities (JLab 12 GeV Upgrade, RHIC Spin, CERN COMPASS, LHC). A brief summary of the EIC machine concepts proposed by BNL and JLab and their basic parameters (energies, luminosity) will be presented, as well as the status and directions of the RD effort.   

The Electron-Ion Collider at BNL: Capabilities and Physics Highlights

Nuclei probed in DIS and dffractive processes in the high-energy (low-$x$) regime open a new precision window into fundamental questions in QCD. The proposed Electron-Ion Collider at BNL (eRHIC) is a new high-energy and high-luminosity electron-ion/proton machine. The proposed design provides unprecedented access to study deeply the nature of QCD matter and strong color fields. It will allow us to explore gluon saturation, one of the outstanding fundamental problems in QCD, and test the validity of the Color Glass Condensate approach. We will outline the compelling physics case for e+A collisions at eRHIC, and discuss briefly the status of machine and detector design concepts.   

Detector Studies for an Electron Ion Collider

A proposal has been made to build an Electron-Ion Collider (EIC) in the US in the next decade, capable of running at multiple electron and ion energies and capable of ion species up to Uranium. One of the important aspects of this programme is the ability to have a detector which is suitable for all energies and species. It must also be able to perform a number of difficult measurements, notably including very forward lepton and ion measurements. In this presentation I will outline the MC studies performed with the aim of designing a detector suitable for use at an EIC.   

The nucleon structure, what an Electron-Ion Collider will teach us

The question after the individual parton (quarks and gluons) contributions to the spin of the nucleon is even after 20 years of experimental efforts not yet solved. After several precise measurements in polarized DIS it is clear, that the spin of the nucleon cannot be explained by the contribution of the quarks alone. This is affirmed by the newest results from COMPASS, HERMES and JLAB on the inclusive spin structure function g1 and on the individual contributions from the different quark flavors from semi-inclusive DIS data. Measurements from the polarized pp-collider RHIC show that also the contribution from gluons is smaller than originally expected. Recent experimental evidence of exclusive reactions, especially DVCS, allows in the formalism of generalized parton distributions the study of an other nucleon spin component the orbital angular momentum. The most recent results on indications of the size of the orbital angular momentum of quarks from data and lattice measurements indicate a small contribution from quark orbital angular momenta to the spin of the proton. At the EIC it will not only be possible to measure all these contributions to the spin of the nucleon with unseen precision, but more importantly the range of all observables can be extended to smaller Bjoerken x, which allows to minimize the biggest uncertainty in these observables, the extrapolation to the unmeasured low-x region.   

Nucleon structure studies through exclusive reactions with an EIC at JLab

Hadrons in QCD are relativistic many-body systems, with a fluctuating number of elementary quark/gluon constituents and a very rich structure of the wave function, with distinct components in different kinematic regions. The 12 GeV energy upgrade at Jefferson Lab will allow a detailed study of the valence quark component. With an EIC at Jefferson Lab we enter the region where the many-body nature of hadrons, coupling to vacuum excitations, etc., become manifest. In this talk I will discuss the exciting prospects of studying the landscape of nucleon structure using exclusive reactions, and in particular the gluon and sea quark imaging of the nucleon.   

The Nucleon Form Factors measurement at EIC

The large luminosity of EIC will provide a unique possibility to study the proton and the neutron at very large momentum transfer where the QCD predictions could be tested. A nucleon Form Factor experiment up to 50 GeV$^{2}$ at EIC will be discussed.   

Possibility for a New Measurement of the Proton Elastic Form Factor Ratio at Very Low $Q^2$

The proton form factors at low $Q^2$ encode information about the peripheral structure of the proton as well as the interplay between the magnetic and electric charge distributions. Furthermore, low $Q^2$ form factor measurements impact high precision experiments, for example, the measurement of the hydrogen hyperfine splitting. Polarization transfer and beam target asymmetry measurements allow to determine the electric to magnetic form factor ratio with high precision down to $Q^2 \simeq 0.15$ GeV$^2$. A recently completed experiment at JLab has recently taken data with unprecedented precision down to $Q^2\simeq 0.3$ GeV$^2$, with a further experiment approved to extend the $Q^2$ range down to 0.015 GeV$^2$. At even lower $Q^2$ the beam-target asymmetry method is impeded by the need to detect either a very forward electron or to use a low energy beam which must traverse the high magnetic field of a polarized target. A recoil polarization measurement at lower $Q^2$ is impossible due to the very low energy of the recoil proton. We suggest an alternative measurement using colliding proton and electron beams which will allow a measurement of the form factor ratio to extremely low $Q^2$ ($\sim 10^{-4}$ GeV$^2$). The opportunity for this measurement will be discussed.   

Delta-Isobar Production in the Hard Photodisintegration of a Deuteron

Hard photodisintegration of the deuteron in delta-isobar production channels is proposed as a useful process in identifying the quark structure of hadrons and of hadronic interactions at large momentum and energy transfer. The reactions are modeled using the hard re scattering model, HRM, following previous works on hard breakup of a nucleon nucleon (NN) system in light nuclei. Here,quantitative predictions through the HRM require the numerical input of fits of experimental NN hard elastic scattering cross sections. Because of the lack of data in hard NN scattering into $\Delta$-isobar channels, the cross section of the corresponding photodisintegration processes cannot be predicted in the same way. Instead, the corresponding NN scattering process is modeled through the quark interchange mechanism, QIM, leaving an unknown normalization parameter. The observables of interest are ratios of differential cross sections of $\Delta$-isobar production channels to NN breakup in deuteron photodisintegration. Both entries in these ratios are derived through the HRM and QIM so that normalization parameters cancel out and numerical predictions can be obtained.   

Expected improvements in polarized parton distribution uncertainties from, proposed, Electron Ion Collider using a Global analysis approach.

Parton distribution functions (PDFs) are indispensable in any calculation of high energy processes involving hadrons. Global analysis of all the experimental data over a wide range of longitudinal momentum fraction of the partons, $x$, and a well resolved momentum scale, $Q^2$, is a way to extract the PDFs. A high luminosity ($>10^{33-34}$ $cm^{-2} s^{-1}$), high energy ($\sqrt(s)$ = 30 to 100 GeV) Electron-Ion-Collider (EIC) will allow to access the kinematic regime between that of HERA and of the fixed-target experiments with much higher statistics. Thus a global analysis including the EIC data will allow us to precisely determine the PDFs in a larger kinematic region. Since EIC will run with a polarized nucleon beam, an extraction of gluon polarization, $\Delta G$, using global analysis will be a major goal for the spin community at this facility. We will present results and improvements in uncertainties we can expect, coming from EIC, on polarized PDFs from global analysis.   

Session D9: Physics Research at the LHC

LHC Physics Potential {\em vs.} Energy

Parton luminosities are convenient for estimating how the physics potential of Large Hadron Collider experiments depends on the energy of the proton beams. I present parton luminosities and ratios of parton luminosities for $gg$, $u\bar{d}$, and $qq$ interactions over the energy range relevant to the Large Hadron Collider, along with example analyses for specific processes.   

Search for Pair Production of First Generation Scalar Leptoquarks at the CMS Experiment

Leptoquarks are theoretical particles carrying both lepton number and quark flavor. They are predicted to exist by Grand Unified Theories, technicolor and composite models, among others. Early results from the search for pair production of first generation scalar leptoquarks at the CMS experiment at the CERN LHC $pp$ collider are presented. Both the discovery potential and exclusion limit for CMS with $pp$ collisions at a center of mass energy of $\sqrt{s}$ = 7 TeV are explored.   

Search for Supersymmetry in the Same-Sign Dilepton Channel with the CMS detector

Events with same-sign dileptons, high $p_T$ multijets and large missing energy represent a very low Standard Model background at the LHC. In regions of the Supersymmetry parameter space which are accessible in the first $100$ $pb^{-1}$ of integrated luminosity, there are expected to be low momentum leptons which are not strongly isolated from the rest of the event. Using a pseudo-data sample of 10 TeV pp collisions reconstructed by a full simulation of the CMS detector, we will present a search for an excess of low momentum same-sign dilepton events over a data driven estimate of the background.   

SUSY searches at ATLAS in di-jet and multi-jet channels using alternatives to missing transverse energy

We investigate the possibilities of discovering Supersymmetry (SUSY) in the di-jet and multi-jet channels using the ATLAS detector at the LHC with $\sqrt {s}=10$ TeV. This analysis investigates alternatives to reconstructed missing transverse energy ($E_T^{Miss}$) as the signature for LSP production in SUSY events, since ($E_T^{Miss}$) may be difficult to measure accurately during early data taking. Such alternative techniques of constructing kinematic variables can be used to search for new physics channels that produce jets and weakly interacting stable particles. We explore a number of kinematic variables to study the discovery significance for various SUSY models with $200 pb^{-1}$ of integrated luminosity. In this talk I will present the work we have done towards the goal to study and understand if any one or combination of these variables can be used in place of, or in conjunction with $E_T^{Miss}$, to yield better discovery significance.   

Plans to Search for New Particles Decaying to Dijets at CMS

The Compact Muon Solenoid (CMS) is one of two multi-purpose detectors which is located on the Large Hadron Collider (LHC) at CERN. We use a generated pseudo-data sample corresponding to $10$ $pb^{-1}$ of integrated luminosity at a pp collision energy of 10 TeV to test CMS plans to search for new particles decaying to two high energy jets (dijets). By construction the measured dijet mass spectrum agrees with the QCD prediction. Applying our search to this pseudo-data sample, we set upper limits on the cross section for dijet resonances. This analysis shows that CMS will be sensitive to new particles decaying to dijets, and if we measured this pseudo-dataset produced from QCD alone, we would exclude at 95\% confidence level the following new particles: axigluons and flavor universal colorons with mass below $1.8$ $TeV$, excited quarks with mass below $1.8$ $TeV$ and E$_{6}$ diquarks with mass below $1.0$ $TeV$ and mass between $1.3$ $TeV$ and $1.7$ $TeV$.   

MUSiC - Model-independent search for deviations from Standard Model predictions in CMS

We present an approach for a model independent search in CMS. Systematically scanning the data for deviations from the standard model Monte Carlo expectations, such an analysis can help to understand the detector and tune event generators. By minimizing the theoretical bias the analysis is furthermore sensitive to a wide range of models for new physics, including the uncounted number of models not-yet-thought-of. After sorting the events into classes defined by their particle content (leptons, photons, jets and missing transverse energy), a minimally prejudiced scan is performed on a number of distributions. Advanced statistical methods are used to determine the significance of the deviating regions, rigorously taking systematic uncertainties into account. A number of benchmark scenarios, including common models of new physics and possible detector effects, have been used to gauge the power of such a method.   

MSSM $\mathbf{H^\pm \rightarrow \chi^\pm \chi^0}$ Searches

\def\met{\mbox{$\rm {\hbox{E\kern-0.5em\lower-.1ex\hbox{/}}}_T$}} In the Minimum Supersymmetric Standard Model (MSSM), the charged Higgs boson ($ H^\pm$) can decay into a chargino-neutralino ($\chi^\pm \chi^0 $) pair producing the final states containing three leptons (electron/muon) and missing transverse energy ($3l+\met$). The early ATLAS data of approximately $200\ pb^{-1}$ can be investigated to determine the $3l+\met$ background shapes for numerous new physics searches beyond the SM. Monte Carlo studies related to such background determination in $3l+\met$ channel along with a preliminary sensitivity study for the MSSM $H^\pm \rightarrow \chi^\pm \chi^0 \rightarrow 3l+\met$ search are presented here.   

Measurement of Missing Transverse Energy using the ATLAS Detector at the Large Hadron Collider

An important experimental signature for many physics processes to be studied with the ATLAS detector at the Large Hadron Collider (LHC) is missing transverse energy, $E_{T}^{Miss}$. The energy carried away by weakly or non-interacting particles such as neutrinos produced in particle collisions is inferred from an imbalance in the vector sum of energy measured transverse to the proton beam axis, the $E_{T}^{Miss}$. Many theories predict the production of new neutral, stable, and weakly interacting particles in LHC collisions. A signature of such a particle's production would be $E_{T}^{Miss}$. In this talk, the design of the ATLAS $E_{T}^{Miss}$ reconstruction software algorithms will be presented, along with performance studies using simulated and cosmic-ray data collected by the ATLAS detector.   

Session D10: Precision Measurements on Atomic and Subatomic Systems

Blackbody-radiation shifts in optical frequency standards with trapped ions

The SI unit of time, the second, is defined in terms of the microwave transition frequency between the two hyperfine levels of the ground state of $^{133}$Cs. Recent advancements in experimental techniques such as laser frequency stabilization, atomic cooling and trapping, etc. have made possible the realization of the second to a precision that is six decades higher than that of the existing standard, by use of optical {\it v.s.} microwave transitions. At optical frequencies, the transition levels are members of different electronic configurations, and one of the largest contributors to the uncertainty budget is the blackbody radiation (BBR) frequency shift. We report BBR shifts of the Ca$^+ 4s - 3d_{5/2}$ and Sr$^+ 5s - 4d_{5/2}$ clock transitions as calculated by the relativistic all-order method, in which all single and double excitations of the Dirac-Fock wave function are included to all orders of perturbation theory. Additional calculations are conducted for the dominant contributions in order to evaluate some omitted high-order corrections and estimate the uncertainty of our final values. Our results for these shifts are an order of magnitude more accurate than previous estimates and are of sufficient accuracy at the present stage of development of trapped-ion optical frequency standards.   

Preparation of the anapole moment measurement in a chain of isotopes

We present the current status of the experimental effort towards the measurement of the anapole moment in different isotopes of francium. The anapole is a parity violating, time reversal conserving nuclear moment that arises from the weak interaction among nucleons, and should be sensitive to the changes in the nuclear structure configuration among the isotopes. The anapole is a unique probe of the weak interaction in the presence of the strong interaction. The system is currently being tested with rubidium and we have analyzed the sensitivity to measurements with a chain of Rb isotopes. Our experimental scheme involves a collection of cold atoms in a blue-detuned dipole trap located at the anti-node of a microwave cavity. The standing wave would drive a parity forbidden E1 transition between hyperfine ground states, interfering with an allowed transition. The rate of transitions depends on the positive or negative handedness of the apparatus and the measurement of their difference is proportional to the anapole moment. The experiment will use of the ISAC radioactive beam facility at TRIUMF.   

$^3$He comagnetometer readout for the neutron electric dipole moment (nEDM) experiment at SNS

The nEDM collaboration is developing a new experiment to measure the neutron's electric dipole moment to $~\sim 10^{-28}$~e--cm. A non-zero neutron EDM would be the first observation of CP violation in a baryon containing only light quarks, while a null result would be inconsistent with predictions from most variants of supersymmetry. The experiment will measure the difference in spin precession, of polarized ultracold neutrons (UCN) produced and stored in a superfluid-helium-filled cell, when the magnetic and electric fields are parallel and antiparallel. A key feature of the experimental method is the use of polarized $^3$He atoms within the cell acting as both spin analyzer and comagnetometer to the UCN. In one mode of running, the $^3$He precession signal is detected by SQUID gradiometers adjacent to the cell. This talk will cover the efforts of the nEDM collaboration towards practical implementation of SQUIDs for the $^3$He comagnetometer readout, with a goal of $\leq 1\ {\rm fT/\sqrt{Hz}}$ noise level (referred to one gradiometer loop), low enough to be a small contribution to the overall uncertainty of the final nEDM result.   

Neutron interferometric precision measurement of the n-$^3$He incoherent scattering length

A new high precision measurement of the incoherent neutron-$^3$He scattering length was recently done at the NIST Neutron Interferometry and Optics Facility. Precision measurements of neutron scattering lengths are an important test of nucleon-nucleon (NN) and three nucleon interaction (3NI) models. In general, theoretical models have failed to agree with experimentally determined scattering lengths for systems with greater than two nucleons. The scattering length for the n-$^3$He system is particularly interesting because large spin-dependent effects make it a unique test of three-nucleon and four-nucleon interactions. Our result of $b_i^\prime = -2.429 \pm$ 0.012 (stat.) $\pm$ 0.014 (syst.) fm was obtained by comparing the phase shift caused by a polarized $^3$He sample for two different neutron spin states using an interferometer. This result and other recent experimental measurements of n-$^3$He scattering lengths will be compared with current NN+3NI models.   

Precision neutron polarimetry for a measurement of the n-$^3$He incoherent scattering length of $^3$He

In a recent experiment, we performed a precision measurement of the incoherent scattering length for neutrons in $^3$He at the Neutron Interferometry and Optics Facility (NIOF) at the National Institute of Standards and Technology (NIST). As part of this experiment, the neutron polarization produced by a supermirror in a monochromatic neutron beam and the efficiency of a precession coil spin flipper were measured to better than 0.1\% relative standard uncertainty using polarized $^3$He spin filter analyzers. Two related, but not identical, approaches were employed: the asymmetry method, in which we determined the asymmetry in the transmission of neutrons through the $^3$He, and the \textquotedblleft normalized transmission\textquotedblright method, in which we determined the transmission asymmetry for polarized vs. unpolarized neutrons. (The latter is often referred to as the shim method in neutron scattering, in which a ferromagnetic shim is typically employed to depolarize the beam.) In both cases we employed reproduceable translation of the supermirror so as to permit determination of the $^3$He analyzing power via neutron transmission measurements, and adiabatic fast passage nuclear magnetic resonance to invert the $^3$He polarization. Results from the two methods will be discussed.   

Decoherence Free Neutron Interferometery

Matter wave optics provide deep insights into quantum mechanics, and in particular matter wave interferometers have served as important examples of macroscopic quantum coherence. Here we show that matter wave optics can benefit from concepts of quantum information processing. We show that a Decoherence Free (DF) matter wave interferometer that was designed based on a quantum error correction code is much less sensitive to mechanical vibrations than is the standard Mach-Zehnder (MZ) interferometer. Matter wave interferometers in general are extremely sensitive to environmental noise, including vibrations, and as a result are only rarely used. The sensitivity to vibrations is a result of the slow velocities of matter waves. Just as neutron interferometer assisted in the development of our current understanding of foundational issues in quantum mechanics, it is well suited to leading the practical implementation of improved coherent control through quantum information theory. We foresee that these changes can make neutron interferometry more available and extend applications in important fields such as soft condensed matter and spintronics.   

Spin Dependent Absorption Cross Section of Neutron $^3He$

Measurement of neutron scattering lengths for light nuclei provides a good opportunity to test theories of nucleon-nucleon and three-nucleon forces. The largest systematic uncertainty for recent measurements of the neutron-$^3He$ incoherent scattering length originates from lack of precise knowledge of the spin dependent abosorption cross section (SDACS). To measure the SDACS to $\sim$0.1\%, the primary experimental challenge is to measure the $^3He$ polarization to the same precision. We are developing a new approach to measure the polarization based on the free induction decay (FID) method. The $^3He$ gas, sealed in a special T-shape cell, is polarized with the spin exchange optical pumping method. The polarized $^3He$ nuclei, which are magnetic dipoles, can induce a classical magnetic field. By using the $^3He$ itself as a magnetometer, the Larmor frequency of the $^3He$ can be measured with FID method. We have chosen a special T-shape for the cell that allows for a calculable magnetic field from the $^3He$ gas while also permitting acceptable neutron transimission. If we flip the polarized $^3He$ 1$80^{\circ}$, the magnetic field will change and therefore the Larmor frequency of $^3He$ will change also. With this method, the polarization of $^3He$, and then the SDACS of n+$^3He$ can be measured to high precision.   

Search For Dinucleon Decay Into Kaon Modes Using Multivariate Techniques

The final results of a search for dinucleon decay into kaon modes ($\it{e.g.}$ pp $\rightarrow$ K$^{+}$K$^{+}$, in $^{16}$O) in the Super-Kamiokande detector, are presented. Multivariate techniques are used to maximize search sensitivity. These dinucleon decay modes are motivated by R-Parity violating modes of Supersymmetry, and can be used to constrain the parameter $\lambda''_{uds}$.   

A New Beam Modulation Strategy for the Q$^{p}_{weak}$ Experiment

A new, robust strategy is presented for beam modulation in the Q-weak experiment. The objective of the Q-weak experiment is to measure the weak charge of the proton via the parity violating asymmetry ($<$ 1ppm) in elastic e-p scattering. The e-p scattering rate largely depends on five beam parameters: horizontal position (X), angle (X), vertical position (Y), angle (Y), and beam energy (E). Changes in these beam parameters when the beam polarization is reversed will create false asymmetries. Although we will attempt to keep changes in beam parameters during reversal as small as possible, we will also measure beam parameter differences and correct the false asymmetries. To do this, we will modulate X, X, Y, Y using four air-core dipoles in the Hall C beamline and measure the beam sensitivities. (We will also modulate beam energy using an SRF cavity.) Two air-core dipoles separated by $\sim $10m will be pulsed at a time to produce relatively pure position or angle changes at the target, for virtually any tune of the beamline. Some preliminary tests of the air-core coils and the associated control instrumentation will be discussed.   

Session D11: SPS Undergraduate Research II

Introductory Physics Experiments Using the Wii Balance Board

The Wii, a video game console by Nintendo, utilizes several different controllers, such as the Wii remote (Wiimote) and the balance board, for game-playing. The balance board was introduced in early 2008. It contains four strain gauges and has Bluetooth connectivity at a relatively low price. Thanks to available open source code, such as GlovePie, any PC with Bluetooth capability can detect the information sent out by the balance board. Based on the ease with which the forces measured by each strain gauge can be obtained, we have designed several experiments for introductory physics courses that make use of this device. We present experiments to measure the forces generated when students lift their arms with and without added weights, distribution of forces on an extended object when weights are repositioned, and other normal forces cases. The results of our experiments are compared with those predicted by Newtonian mechanics.   

Galileo on Two Wheels: Why Does Newton Make Me Keep Pedaling This Thing?

As part of an effort to use examples for the bicycle to illustrate basic physics principles, we have been exploring the application of Newton's laws of motion to a moving bicycle. In particular, we have developed methods to measure the bicycle's two primary forces of resistance-tire rolling resistance and air resistance on rider and bike. With the use of minimal equipment such as stopwatches and bicycle speedometers, we have obtained data that provide a very good fit to simple models and closed differential equation solutions. We have also found that the bicycle affords a simple, low tech, and convenient method to study concepts of terminal velocity and rolling resistance. Just as Galileo made use of inclined planes to study falling objects, we used gently sloping hills to determine forces on the moving bicycle. Our methods make use of a novel technique to determine the bicycle and rider frontal cross sectional area. We hope our methods and results will be of interest to students of physics and mathematics and to the general cycling community. We have found it is possible for a cyclist to easily measure; without the use of expensive time in a wind tunnel; the effects of various body positions on wind resistance. This paper also examines the force and power consequences of riding at high speeds.   

Classical Mechanics Experiments using Wiimotes

The Wii, a video game console, is a very popular device. Although computationally it is not a powerful machine by today's standards, to a physics educator the controllers are its most important components. The Wiimote (or remote) controller contains a three-axis accelerometer, an infrared detector, and Bluetooth connectivity at a relatively low price. Thanks to available open source code, such as GlovePie, any PC or Laptop with Bluetooth capability can detect the information sent out by the Wiimote. We present experiments that use two or three Wiimotes simultaneously to measure the variable accelerations in two mass systems interacting via springs. Normal modes are determined from the data obtained. Masses and spring constants are varied to analyze their impact on the accelerations of the systems. We present the results of our experiments and compare them with those predicted using Lagrangian mechanics.   

The Effects of Fluid Absorption on the Mechanical Properties of Joint Prostheses Components

Ultra-high-molecular-weight polyethylene (UHMWPE) is the material playing the role of cartilage in human prosthetic joints. Wear debris from UHMWPE is a common reason for joint arthroplasty failure, and the exact mechanism responsible for wear remains an area of investigation. In this study, the microstructure of UHMWPE was examined as a function of fluid absorption. Samples with varying exposure to e-beam radiation (as part of the manufacturing process) were soaked for forty days in saline or artificial synovial fluid, under zero or 100 lbs load. Samples were then tensile-tested according to ASTM D-3895. The post-stressed material was then examined by transmission electron microscopy to evaluate the molecular response to stress, which correlates with macroscopic mechanical properties. Three parameters of the crystalline lamellae were measured: thickness, stacking ratio, and alignment to stress direction. Results indicate that fluid absorption does affect the mechanical properties of UHMWPE at both the microscopic and microscopic levels.   

Optical Tweezing of Yeast Cells

Optical Tweezers is a powerful technique that aids in understanding and applying the unique principles of photonics, optical physics, and basic cell biology. The experiments presented involve using HeNe lasers (632.8 nm) to trap spherical and ovular shaped objects in a solution. Polystyrene spheres, six micrometers in diameter, were trapped and moved with the laser to calibrate our system. The spheres were submerged in a Sodium Phosphate buffer solution to prevent sticking. Saccharomyces cerevisae, better known as yeast, was grown in a glucose rich environment to reach sizes of four to nine micrometers. Our optical tweezers captured and moved these cells under the operators command. A two laser system was utilized to control two cells simultaneously and attempt the splitting of cells.   

Raman Spectroscopy of Cocrystals

Cocrystals are a class of compounds that consist of two or more molecules that are held together by hydrogen bonding. Pharmaceutical cocrystals are those that contain an active pharmaceutical ingredient (API) as one of the components. Pharmaceutical cocrystals are of particular interest and have gained a lot of attention in recent years because they offer the ability to modify the physical properties of the API, like solubility and bioavailability, without altering the chemical structure of the API. The APIs that we targeted for our studies are theophylline (Tp) and indomethacin (Ind). These compounds have been mixed with complementary coformers (cocrystal former) that include acetamide (AcONH2), melamine (MLM), nicotinic acid (Nic-COOH), 4-cyanopyridine (4-CNPy) and 4-aminopyridine (4-NH2Py). Raman spectroscopy has been used to characterize these cocrystals. Spectra of the cocrystals were compared to those of the coformers to analyze for peak shifts, specifically those corresponding to hydrogen bonding. A 0.5 m CCD Spex spectrometer was used, in a micro-Raman setup, for spectral analysis. An Argon ion Coherent laser at 514.5 nm was used as the excitation source.   

Comparison of Sprite-Halo Characteristics Imaged Over the USA and South America

Sprites and Halos are prominent members of an extraordinary family of Transient Luminous Events (TLEs) that have been discovered over the past 20 years. Halos are short-lived (few millisecond) diffuse optical emissions that appear as horizontal bright disks suspended above distant thunderstorms. They frequently precede the formation of a vertically structured sprite. Reports of halos are relatively few and indicate a limited height range centered at approximately 80 km with optical diameters up to about 100 km. Unlike sprite events, which occur almost exclusively in association with large positive cloud-to-ground lightning discharges, halos have recently been observed from satellites in association with both positive and negative discharges. This presentation compares the optical and electrical properties of a large number of halos and sprite-halos imaged over the U.S. Great Plains and over Northern Argentina in South America. Our goal is to improve current knowledge of their characteristics and variability.   

Examination of wave band pattern feature observed in northwestern Monterey Bay airborne imagery during the 2009 SARP project

On July 22, 2009, MASTER data was obtained from the DC-8 flying laboratory over the Monterey Bay region, and an unusual banded wave structure was observed in the northwest corner of the bay, approximately half a kilometer off-shore. This structure consisted of alternating dark and light bands, each 350 meters wide and 1500 meters long. Three possible explanations for the nature of the phenomenon were proposed: Langmuir cells, internal waves, or the small scale atmospheric-ocean interaction in the form of wind jets and supercritical airflow. ENVI, Excel, MATLAB and Google Earth programs were used to analyze the data. Results of this analysis were then examined in light of each of the three theories, in order to determine which explanation is more or less likely. The effect of the feature on the biological and chemical make-up of the immediately adjacent area was also studied through the in-situ data of the ocean surface layer collected by boat in Monterey Bay. If the bands observed alter physical conditions in some way that could affect the biology of the area, it is important to understand the nature of those bands and to see whether or not their presence introduces any significant change.   

Astronomical Dating of Edvard Munch's Summer Sky Paintings

Norwegian painter Edvard Munch, most famous for \textit{The} \textit{Scream,} created many spectacular works depicting the skies of Norway. Our Texas State group used astronomical methods to analyze three of these paintings: \textit{Starry Night}, \textit{The Storm,} and \textit{Sunrise in Asgardstrand}. Astronomical dating of these paintings has some importance because the precise days when Munch visited Asgardstrand are unknown. Our research group traveled to Norway in August 2008 to find the locations from which Munch painted these three works. We then used astronomical calculations, topographical analysis, historical photographs, and weather records to determine the precise dates and times for the scenes depicted in these paintings.   

Session D12: Rare B Decays, B-Baryon

A search for baryon and lepton number violation in $B$ decays using the BaBar dataset

A search is performed for the decay $B \rightarrow \textrm{baryon } \textrm{lepton}$, where the baryon is either a $\Lambda_c^+$ or $\Lambda^0$ and the lepton is a muon or electron. This decay would violate baryon (B) and lepton (L) number individually. In some of the decays in which we search, the difference (B-L) is conserved. The $B-L$-conserving process is generally interpreted as being mediated by a boson that carries both color and lepton number and is fractionally charged. This boson is a signature of some unification theories. The flavor/generation dependence of this type of interaction can be constrained by a comprehensive search for decays involving different flavors of quarks and leptons. At the SLAC National Accelerator Laboratory, the PEP-II storage rings provided $e^+/e^-$ beams from 1999-2008, during which time the {\sl B{\scriptsize A}B{\scriptsize AR}} experiment collected 429 fb$^{-1}$ of data at the $\Upsilon(4S)$ resonance giving this analysis access to 1 billion $B$ mesons. In the event of a null result, upper limits on the $B$ branching fractions for these processes will be calculated in order to provide experimental constraints. The status of the search will be presented.   

Search for $B\rightarrow\nu\overline{\nu}(\gamma)$

We present a search for the decay $B\rightarrow\nu\overline{\nu}(\gamma)$ in $\Upsilon (4S)\rightarrow B\kern 0.18em\overline{\kern -0.18em B}$ decays recorded with the {\sl B{\scriptsize A}B{\scriptsize AR}} detector at the PEP-II asymmetric-energy $B$ factory at SLAC. The Standard Model predictions for the $B\rightarrow\nu\overline{\nu}(\gamma)$ branching fractions are far from the current experimental sensitivities, but many New Physics Models predict significant enhancements. A sample of events in which one $B$ is reconstructed in $B^{0}\rightarrow D(^{*})l\nu$ modes is selected, and in the recoil a search for a $B$ decaying to purely invisible final states or to a photon plus missing energy is performed. In order to reject background a number of kinematic and shape selection criteria are used. Features of the signal signature are exploited by imposing constraints on signal variables such as track multiplicity, neutral energy and missing momentum. We describe the search techniques and provide the most recent results from {\sl B{\scriptsize A}B{\scriptsize AR}}.   

Study of charmless semileptonic $B$ decays at {\sl B{\scriptsize A}B{\scriptsize AR}}

We present an analysis of charmless semileptonic $B$-meson decays recorded with the {\sl B{\scriptsize A}B{\scriptsize AR}} detector at the $\Upsilon(4S)$ resonance. We measure branching fractions for the exclusive modes $B \rightarrow (\pi/\rho/\omega) \ell \nu$. We compare the measured distribution in $q^2$, the momentum-transfer squared, with theoretical predictions based on lattice QCD, light-cone sum rules, and quark model form factor calculations. We also extract the CKM matrix element $|V_{ub}|$ from $B \rightarrow \pi\ell\nu$ decays.   

Measurement of Forward-Backward Asymmetry in $B\to K^{(*)}\mu\mu$ and Search for $B_s^0\to \phi\mu\mu$ at the CDF Experiment

We report results on the measurement of the forward-backward asymmetry ($A_{\rm FB}$) in $B\to K^{(*)}\mu\mu$. $A_{\rm FB}$ may imply new physics beyond the standard model via the loop structure in the decay. The data set is collected with the CDF II detector using $p\bar{p}$ collisions produced at the Fermilab Tevatron. $A_{\rm FB}$ is extracted from a muon angular distribution in dimuon restframe. We also present a search result for $B_s^0\to \phi\mu\mu$ that is not observed so far.   

Measurement of $\Sigma_b$ Baryons with CDF II Detector

In 2006 CDF Collaboration reported a first observation of bottom baryon states $\Sigma_{b}$. Based on $\sim$~5.0~fb$^{-1}$ of CDF data we present a high statistics measurements of strongly decaying b-baryons based on a data sample of fully reconstructed $\Lambda_{b}$ decays collected by CDF~II detector at $\sqrt{s} = 1.96$~TeV in several trigger paths. The confirmation of the discovery and the first independent mass and widths measurements of all four states $\Sigma_{b}^{(*)+}$ and $\Sigma_{b}^{(*)-}$ will be presented.   

Session D13: Ground-based and Space-based Instruments and Techniques

Current Status of QUIET

QUIET (the Q/U Imaging ExperimenT) is designed to measure the Cosmic Microwave Background polarization on large angular scales using sensitive HEMT-based polarimeters. The experiment targets the signature on the CMB of gravitational waves generated during inflation, known as B-mode polarization. Observations were made from October 2008 through May 2009 using a 19-element 40 GHz instrument coupled to a 1.4 meter telescope located at the Chajnantor Observatory in Chile. Observations with a 90-element 90 GHz instrument on the same telescope are ongoing. We describe the status of analysis of the 40 GHz data and the current 90 GHZ observations. At both frequencies, we target four patches totaling $\sim$1000 square degrees and chosen to have low foreground contamination. The current phase of QUIET will provide precise measurements of the E-mode polarization power spectrum and improve upper limits on B-modes for angular scales up to $\ell=1000$. Meanwhile, planning is underway for the second phase of QUIET, which will increase the number of detector by an order of magnitude to reach the level of sensitivity necessary to detect B-mode polarization.   

The Science and Design of the AGIS Observatory

The AGIS observatory is a next-generation array of imaging atmospheric Cherenkov telescopes (IACTs) for gamma-ray astronomy between 100~GeV and 100~TeV. The AGIS observatory is the next logical step in high energy gamma-ray astronomy, offering improved angular resolution and sensitivity compared to FERMI, and overlapping the high energy end of FERMI's sensitivity band. The baseline AGIS observatory will employ an array of 36 Schwarzschild-Couder IACTs in combination with a highly pixelated (0.05$^{\circ}$ diameter) camera. The instrument is designed to provide millicrab sensitivity over a wide (8$^{\circ}$ diameter) field of view, allowing both deep studies of faint point sources as well as efficient mapping of the Galactic plane and extended sources. I will describe science drivers behind the AGIS observatory and the design and status of the project.   

Toward Supernova Observations with the Micro-X High-Resolution Microcalorimeter X-ray Imaging Rocket

The Micro-X High-Resolution Microcalorimeter X-ray Imaging Rocket is a sounding rocket payload which will observe extended astrophysical X-ray sources with a focal plane array of transition-edge sensor microcalorimeters. An energy resolution of 2--4 eV over the 0.2--3.0 keV band, coupled with a $\sim~300$~cm$^2$ conical approximation Wolter-I mirror, will make high energy resolution imaging of extended sources possible. Puppis A, a bright supernova remnant, will be the first target. The line-dominated expected spectrum of the recently discovered ``silicon knot'' of Puppis A will provide a wealth of new information. Highly resolved Doppler shifts and broadening of emission lines will map out the dynamical structure of the ejecta. The ionization state of the plasma across the knot and between elements will be analyzed with the benefit of fewer model degeneracies. Additionally, estimates of elemental abundances in the remnant will be refined, and the spatial variations of enrichment across the knot will be mapped. The first flight is scheduled for January 2011. We will give an overview of the science goals and an update on our current progress.   

A tunable laser system for precision wavelength calibration of spectra

We present a novel laser-based wavelength calibration technique that improves the precision of astronomical spectroscopy, and solves a calibration problem inherent to multi-object spectroscopy. We have tested a prototype with the Hectochelle spectrograph at the MMT 6.5 m telescope. The Hectochelle is a high-dispersion, fiber-fed, multi-object spectrograph capable of recording up to 240 spectra simultaneously with a resolving power of 40000. The standard wavelength calibration method uses of spectra from ThAr hollow-cathode lamps shining directly onto the fibers. The difference in light path between calibration and science light as well as the uneven distribution of spectral lines are believed to introduce errors of up to several hundred m/s in the wavelength scale. Our tunable laser wavelength calibrator is bright enough for use with a dome screen, allowing the calibration light path to better match the science light path. Further, the laser is tuned in regular steps across a spectral order, creating a comb of evenly-spaced lines on the detector. Using the solar spectrum reflected from the atmosphere to record the same spectrum in every fiber, we show that laser wavelength calibration brings radial velocity uncertainties down below 100 m/s. We also present results from studies of globular clusters, and explain how the calibration technique can aid in stellar age determinations, studies of young stars, and searches for dark matter clumping in the galactic halo.   

Photoelectron Track Length Distributions in CH$_{3}$OCH$_{3}$ and Ne:CO$_{2}$:NO$_{2}$CH$_{3}$

We have measured the photoelectron track length distribution in 190 Torr CH$_{3}$OCH$_{3}$ and 400 Torr Ne:CO$_{2}$:NO$_{2}$CH$_{3}$, partial pressures 300:80:20 Torr, using a Time Projection Chamber Polarimeter (TPC) and Negative Ion TPC Polarimeter (NITPC) respectively. The measurements were made at the Brookhaven National Laboratory National Synchrotroon Light Source. Track length means range from 150 microns at 2.5 keV to 700 microns at 6 keV for CH$_{3}$OCH$_{3}$ and 150 microns at 3.0 keV to 700 microns at 7 keV. The track length mean vs energy was found to fit a powerlaw as reported for other gases. We found that for CH$_{3}$OCH$_{3, }$n=1.69 and for Ne:CO$_{2}$:NO$_{2}$CH$_{3,}$ n=1.72. This data has important implications for the design of the readout in future TPC's and NITPC's. TPC's and NITPC's for X-ray polarization were recently developed at NASA GSFC and a CH$_{3}$OCH$_{3}$ TPC will be the main instrument for the GEMS mission, a recently selected NASA SMEX.   

Database and Library Development of Organic Species using Gas Chromatography and Mass Spectral Measurements in Support of the Mars Science Laboratory

Our work involves the development of an organic contaminants database that will allow us to determine which compounds are found here on Earth and would be inadvertently detected in the Mars soil and gaseous samples as impurities. It will be used for the Sample Analysis at Mars (SAM) instrumentation analysis in the Mars Science Laboratory (MSL) rover scheduled for launch in 2011. In order to develop a comprehensive target database, we utilize the NIST Mass Spectral Library, Automated Mass Spectral Deconvolution and Identification System (AMDIS) and Ion Fingerprint Deconvolution (IFD) software to analyze the GC-MS data. We have analyzed data from commercial samples, such as paint and polymers, which have not been implemented into the rover and are now analyzing actual data from pyrolyzation on the rover. We have successfully developed an initial target compound database that will aid SAM in determining whether the components being analyzed come from Mars or are contaminants from either the rover itself or the Earth environment and are continuing to make improvements and adding data to the target contaminants database.   

Non-Linear Simulation for the Disturbance of Electronic Systems in Low Earth Orbits by High Energy Electrons

A Simulator is presented that models the disturbance of electrical circuits by high energy electrons trapped in earth's radiation belts; the model components are a module computing the electron fluence rate given the altitude, the time of the year, and the sunspot number, a module that models the interaction of the electrons with the materials of the electrical component, and a module that computes the charge and the magnitude of electrical field in the insulating materials as a function of time. The Adameic-Calderwood equation is used to model the relationship between the electrical conductivity of dielectric materials and the electric field intensity, making the charging/discharging equations highly non-linear. The non-linearity of the charging equations becomes especially pronounced in magnetic storms during intense solar flares. The results show that the electric field intensity can approach the dielectric breakdown strength in materials commonly used as dielectrics in space-based systems and that the fields can be sustained at high levels for as long as an hour.   

Speed Kills: Highly Relativistic Spaceflight Would be Fatal for People and Instruments

Stories, books and movies about space travel often describe journeys at near-light velocities. Such high speed is desirable, as the resulting relativistic time dilation reduces the duration of the trip, at least for the travelers, so that they can cover interstellar distances in a reasonable amount of time (by their own clocks) and live long enough to reach their destination. The relativistic rocket equation shows the enormous difficulty of achieving such velocities. As spaceship velocities approach the speed of light, interstellar hydrogen, although only present on average at a density of about 2 atoms per cm$^{3}$, impinges on the spacecraft and turns into intense radiation (Purcell, 1963) that would quickly kill passengers and destroy instrumentation. In addition, the energy loss of ionizing radiation passing through the ship's hull represents an increasing heat load which necessitates large expenditures of energy to cool the ship. Preventing this irradiation by the use of material or electromagnetic shields is a daunting and, as far as we know, unsolvable problem. The presence of interstellar hydrogen is yet another formidable obstacle to interstellar travel.   

Session D14: Modeling Black Hole Binaries

Simulations of Binary Black Hole Mergers in Gaseous Environments

Massive black hole mergers in the presence of gaseous accretion flows are prime candidates for simultaneous observations of both gravitational waves and electromagnetic signals. We study such systems using our fully general relativistic hydrodynamics code, focusing on the characterization of potentially observable electromagnetic signatures. We outline preliminary results from our investigations, focusing on binaries which merge inside a large, adiabatic cloud with constant gas density and temperature at infinity. We consider cases in which the binary center of mass is at rest (the ``BHBH Bondi accretion problem'') or moving (the ``BHBH Bondi-Hoyle-Lyttleton accretion problem'') relative to the gas cloud. We find evidence for enhancements in the electromagnetic luminosity over the values for single, isolated BHs. Such enhancements may constitute an observable signal.   

Binary Black Hole Mergers in a Gas Cloud and their Electromagnetic Signatures

Coincident detections of electromagnetic (EM) and gravitational wave (GW) signatures from individual supermassive black hole (SMBH) binary mergers are the next observational grand challenge. Such coincident detections would identify the location of the event to higher accuracy as well as provide a means to study cosmological evolution, accretion processes associated with SMBH binaries, and more generally to tests of underlying principles of general relativity. Understanding conditions under which coinciding EM and GW signatures are expected to arise during coalescence is therefore of paramount importance. As an essential step towards this goal, we present results from the first fully general relativistic, hydrodynamical study of the late inspiral and merger of equal-mass SMBHs with spin $a/M_h \le 0.6$ in a gas cloud.   

Binary black hole initial data with tidal deformations and outgoing radiation

We present initial data for the quasicircular inspiral of a nonspinning black hole binary, including tidal deformations and outgoing radiation. We construct these data by asymptotically matching two perturbed Schwarzschild metrics to a post-Newtonian (PN) metric. We carry out this matching through $O(v^4)$ ($v$ is the binary's orbital velocity) so the data are conformally curved. The PN metric includes both near and radiation zone contributions and uses the 3.5PN results for the binary's past history. Asymptotic matching produces piecewise continuous global data; we smooth the joins using transition functions. The inclusion of tidal deformations and outgoing radiation might ameliorate the initial burst of spurious radiation observed with conformally flat data. Such an improvement might be essential for simulations to provide sufficiently accurate templates for parameter estimation with advanced gravitational wave detectors.   

Numerical simulations of binary black holes with nearly extremal spins

There is a significant possibility that astrophysically realistic black holes may have nearly extremal spins (i.e., spins close to 1 in dimensionless units). The prospect of observing the gravitational waves from a binary-black-hole merger with nearly extremal spins motivates the goal of simulating these systems numerically. These simulations must begin with initial data that satisfy the Einstein constraint equations; however, the commonly used methods of generating constraint-satisfying initial data cannot yield data with nearly extremal spins. In this talk, I will describe evolutions of conformally curved binary-black-hole initial data with nearly extremal spins using the Caltech-Cornell-CITA Spectral Einstein Code (SpEC).   

Extracting physics from numerical spacetimes with constant-expansion surfaces

Extracting unambiguous physical information from a spacetime has long been one of the central issues in General Relativity. Defining unique expressions that are generally covariant and have recognizable physical properties (e.g., obey conservation laws when the appropriate symmetries apply) has proven to be impossible without the introduction of further structure, such as coordinate conditions at null infinity or restrictions on the 2-surfaces to be used for gravitational wave extraction. Inspired by the successes of the Isolated and Dynamical Horizon framework, along with its practical effectiveness in numerical contexts, we discuss the use of general constant-expansion surfaces in the resolution of the ambiguities, and illustrate the results in a few cases of physical interest.   

Comparing binary black hole evolutions using finite difference and spectral methods

We compare waveforms for binary black hole simulations using finite difference with adaptive mesh refinement and spectral methods with multiple domains. In both cases we use the exact same initial data, extracting waves at a fixed location and extrapolating them to infinity.   

Binary Black Hole Mergers in SpEC

The Caltech-Cornell spectral Einstein Code (SpEC) is now able to robustly and accurately evolve binary black hole systems through the inspiral, merger and ringdown phases. This is attributed to new gauge conditions as well as a robustly stable numerical algorithm. The talk will highlight the key new elements of our algorithm.   

Modelling multiple modes of spinning merger waveforms

The Implicit Rotating Source (IRS) ansatz provides a coherent model of the dominant modes of gravitational radiation from a merging black-hole binary. Building on work with unequal-mass nonspinning binaries [Baker et al. Phys. Rev. D vol. 78, 044046 (2008)], we have applied the IRS to mergers of aligned and anti- aligned spinning binaries to form useful multi-mode waveform templates. We also discuss issues of parameter selection and spin and mass measurement with the Goddard Hahndol code.