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Time Dependent Channel Packet Calculation Of Two Nucleon Scattering Matrix Elements, Brian S. Davis 2010 Air Force Institute of Technology

Time Dependent Channel Packet Calculation Of Two Nucleon Scattering Matrix Elements, Brian S. Davis

Theses and Dissertations

A new approach to calculating nucleon-nucleon scattering matrix elements using a proven atomic time-dependent wave packet technique is investigated. Wave packets containing centripetal barrier information are prepared in close proximity to nuclear well. This is accomplished by first using an analytic equation to determine the wave packets in a suitable intermediate asymptotic state where the centripetal barrier is negligible. Then, the split operator technique is used to propagate the wave packets back to their original positions under the full Hamiltonian. Here, one wave packet is held stationary while the other is allowed to evolve and explore the nuclear well. Scattering …


Nuclear Forensics: Measurements Of Uranium Oxides Using Time-Of-Flight Secondary Ion Mass Spectrometry (Tof-Sims), Wesley A. Schuler 2010 Air Force Institute of Technology

Nuclear Forensics: Measurements Of Uranium Oxides Using Time-Of-Flight Secondary Ion Mass Spectrometry (Tof-Sims), Wesley A. Schuler

Theses and Dissertations

Over the past decade, law enforcement, governmental and public agencies have been stymied by the threat of the trafficking of nuclear materials. During this time span, reports from the International Atomic Energy Agency of illicit trafficking have increased eightfold from 20 to 160. For this reason, nuclear forensics is a burgeoning science focused on the identification of seized special nuclear materials. Identification of these materials is based upon the wealth of information that can be obtained by applying multiple analytical and measurement technologies. All of the information gained from each sample can then be used to further characterize other samples …


Three Dimensional Positron Annihilation Momentum Measurement Technique (3dpamm) Applied To Measure Oxygen-Atom Defects In 6h Silicon Carbide, Christopher S. Williams 2010 Air Force Institute of Technology

Three Dimensional Positron Annihilation Momentum Measurement Technique (3dpamm) Applied To Measure Oxygen-Atom Defects In 6h Silicon Carbide, Christopher S. Williams

Theses and Dissertations

A three-dimensional Positron Annihilation Spectroscopy System (3DPASS) capable to simultaneously measure three-dimensional electron-positron (e--e+) momentum densities measuring photons derived from e--e+ annihilation events was designed and characterized. 3DPASS simultaneously collects a single data set of correlated energies and positions for two coincident annihilation photons using solid-state double-sided strip detectors (DSSD). Positions of photons were determined using an interpolation method which measures a figure-of-merit proportional to the areas of transient charges induced on both charge collection strips directly adjacent to the charge collection strips interacting with the annihilation photons. The subpixel resolution was measured for both double-sided strip detectors (DSSD) and …


Thermal Neutron Point Source Imaging Using A Rotating Modulation Collimator (Rmc), Nathan O. Boyce 2010 Air Force Institute of Technology

Thermal Neutron Point Source Imaging Using A Rotating Modulation Collimator (Rmc), Nathan O. Boyce

Theses and Dissertations

This thesis demonstrates a previously untested capability of the Rotating Modulation Collimator (RMC) to image a point-like neutron source. The encouraging results, achieved using low-energy neutrons, provide motivation for further refinement and continued research with higher-energy neutrons. The detector and the masks on an existing RMC imaging system were exchanged to function with neutrons. The source in this research produced a poly-energetic spectrum of neutrons through the reaction. The source of alpha particles was a 72.7 mCi 239Pu source. The RMC detector was located 250 cm from the bare source and operated for three hours to generate a modulation …


In-Situ, Gate Bias Dependent Study Of Neutron Irradiation Effects On Algan/Gan Hfets, Janusz K. Mikina 2010 Air Force Institute of Technology

In-Situ, Gate Bias Dependent Study Of Neutron Irradiation Effects On Algan/Gan Hfets, Janusz K. Mikina

Theses and Dissertations

AlGaN/GaN Heterostructure Field Effect Transistors (HFETs) have come under increased study in recent years due to their highly desirable material and electrical properties and survivability even during and after exposure to extreme temperature and radiation environments. In this study, unpassivated and SiN passivated Al0.27Ga0.73N/GaN HFETs were subjected to neutron radiation at 120 K. The primary focus of the research was the effects of neutron irradiation on drain current, gate leakage current, threshold voltage shift, gate-channel capacitance, and the effects of biasing the gate during irradiation. In-situ measurements were conducted on transistor current, gate-channel capacitance, and gate …


Measurement Of Dijet Photoproduction For Events With A Leading Neutron At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch, I. Brock, H. Hartmann 2010 Argonne National Laboratory

Measurement Of Dijet Photoproduction For Events With A Leading Neutron At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch, I. Brock, H. Hartmann

Faculty Publications

Differential cross sections for dijet photoproduction and this process in association with a leading neutron, e ++p→e ++jet+jet+X(+n), have been measured with the ZEUS detector at HERA using an integrated luminosity of 40 pb -1. The fraction of dijet events with a leading neutron was studied as a function of different jet and event variables. Single- and double-differential cross sections are presented as a function of the longitudinal fraction of the proton momentum carried by the leading neutron, x L, and of its transverse momentum squared, pT2. The dijet data are compared to inclusive DIS and photoproduction results; they are …


High-Energy Amplitudes In N= 4 Sym In The Next-To-Leading Order, Ian Balitsky, Giovanni A. Chirilli 2010 Old Dominion University

High-Energy Amplitudes In N= 4 Sym In The Next-To-Leading Order, Ian Balitsky, Giovanni A. Chirilli

Physics Faculty Publications

The high-energy behavior of the N = 4 SYM amplitudes in the Regge limit can be calculated order by order in perturbation theory using the high-energy operator expansion in Wilson lines. At large Nc , a typical four-point amplitude is determined by a single BFKL pomeron. The conformal structure of the four-point amplitude is fixed in terms of two functions: pomeron intercept and the coefficient function in front of the pomeron (the product of two residues). The pomeron intercept is universal while the coefficient function depends on the correlator in question. The intercept is known in the first two orders …


Differential Cross Section And Recoil Polarization Measurements For The Γp→K+Λ Reaction Using Clas At Jefferson Lab, M. E. McCracken, Gerard P. Gilfoyle, et. al. 2010 University of Richmond

Differential Cross Section And Recoil Polarization Measurements For The Γp→K+Λ Reaction Using Clas At Jefferson Lab, M. E. Mccracken, Gerard P. Gilfoyle, Et. Al.

Physics Faculty Publications

We present measurements of the differential cross section and 'B; recoil polarization for the γpK+Λ reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ and K+p (missing π) final-state topologies; results from these analyses were found to exhibit good agreement. These differential-cross-section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300-MeV increase …


Fission Fragment Isomers Populated Via 6Li+232Th., J. J. Ressler, J. A. Caggiano, C. J. Francy, P. N. Peplowski, J. M. Allmond, C. W. Beausang, L. A. Bernstein, D. L. Bleuel, J. T. Burke, P. Fallon, A. A. Hecht, D. V. Jordan, S. R. Lesher, M. A. McMahan, T. S. Palmer, L. Phair, N. D. Scielzo, P. G. Swearingen, G. A. Warren, M. Wiedeking 2010 University of Richmond

Fission Fragment Isomers Populated Via 6Li+232Th., J. J. Ressler, J. A. Caggiano, C. J. Francy, P. N. Peplowski, J. M. Allmond, C. W. Beausang, L. A. Bernstein, D. L. Bleuel, J. T. Burke, P. Fallon, A. A. Hecht, D. V. Jordan, S. R. Lesher, M. A. Mcmahan, T. S. Palmer, L. Phair, N. D. Scielzo, P. G. Swearingen, G. A. Warren, M. Wiedeking

Physics Faculty Publications

Short-lived isomers in fission fragments following bombardment of 45-MeV 6Li on 232Th were examined. Isomers in the A ~ 95,122, and 132 mass regions were observed. New isomeric decays were observed in 121In [T1/2=17(2) μs], 123In (T1/2≳100 μs), and 125Sb [T1/2=25(4) μs]. These isomers are suggested to arise from ν(h11/2d3/2)7and ν(h11/2s1/2)5 neutron core excitations coupling with the valence proton.


Measurement Of Single-Target Spin Asymmetries In The Electroproduction Of Negative Pions In The Semi-Inclusive Deep Inelastic Reaction N↑(E,Éπ¯)X On A Transversely Polarized 3he Target, Chiranjib Dutta 2010 University of Kentucky

Measurement Of Single-Target Spin Asymmetries In The Electroproduction Of Negative Pions In The Semi-Inclusive Deep Inelastic Reaction N↑(E,Éπ¯)X On A Transversely Polarized 3he Target, Chiranjib Dutta

University of Kentucky Doctoral Dissertations

The experiment E06010 measured the target single spin asymmetry (SSA) in the semiinclusive deep inelastic (SIDIS) n↑(e,éπ¯)X reaction with a transversely polarized 3He target as an effective neutron target. This is the very first independent measurement of the neutron SSA, following the measurements at HERMES and COMPASS on the proton and the deuteron. The experiment acquired data in Hall A at Jefferson Laboratory with a continuous electron beam of energy 5.9 GeV, probing the valence quark region, with x = 0.13→0.41, at Q2 = 1.31→3.1 GeV2. The two contributing mechanisms to the measured asymmetry, viz, the …


Two Particle Correlations And The Ridge In Relativistic Heavy Ion Collisions, George Stevens Moschelli 2010 Wayne State University

Two Particle Correlations And The Ridge In Relativistic Heavy Ion Collisions, George Stevens Moschelli

Wayne State University Dissertations

Measurements at the Relativistic Heavy Ion Collider (RHIC) find an enhancement of two particle correlations in relativistic heavy ion collisions, not present in proton-proton collisions. Because the correlation structure is wide in relative pseudorapidity and narrow in relative azimuthal angle, it is known as the ridge. The most striking feature of the ridge is that it seems to extend to a long range in relative pseudorapidity where causality limits interaction. Similar ridge structures are observed in correlations of particles associated with and without a jet trigger. We argue that the untriggered ridge arises when particles formed in an early Glasma …


Parton Energy Loss In Heavy-Ion Collisions Via Direct-Photon And Charged-Particle Azimuthal Correlations, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, B. D. Anderson, D. Arkhipkin, G. S. Averichev, S. Bueltmann, I. Koralt, STAR Collaboration 2010 Old Dominion University

Parton Energy Loss In Heavy-Ion Collisions Via Direct-Photon And Charged-Particle Azimuthal Correlations, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, B. D. Anderson, D. Arkhipkin, G. S. Averichev, S. Bueltmann, I. Koralt, Star Collaboration

Physics Faculty Publications

Charged-particle spectra associated with direct photon Ydir) and π0 are measured in p+p and Au+Au collisions at center-of-mass energy √sNN=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. A shower-shape analysis is used to partially discriminate between Ydirand π0. Assuming no associated charged particles in the γdir direction (near side) and small contribution from fragmentation photons (Yfrag), the associated charged-particle yields opposite to Ydir(away side) are extracted. In central Au+Au collisions, the charged-particle yields at midrapidity (|η|<1) and high transverse momentum (3 < PTassoc < 16 GeV/c) associated with γdir and π0 (|η|<0.9, 8 < PTtrig <16 GeV/c) are suppressed by a factor of 3–5 compared with p+p collisions. The observed suppression of the associated charged particles is similar for Ydir and π0 and …


A Measurement Of The Neutron Electric Form Factor At Very Large Momentum Transfer Using Polarized Electrons Scattering From A Polarized Helium-3 Target, Aidan Michael Kelleher 2010 College of William & Mary - Arts & Sciences

A Measurement Of The Neutron Electric Form Factor At Very Large Momentum Transfer Using Polarized Electrons Scattering From A Polarized Helium-3 Target, Aidan Michael Kelleher

Dissertations, Theses, and Masters Projects

Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q2 and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized 3He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. GEn was measured …


Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku 2010 Old Dominion University

Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku

Physics Faculty Publications

We present measurements of the charge balance function, from the charged particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au collisions at √sNN = 200 GeV using the STAR detector at RHIC. We observe that the balance function is boost-invariant within the pseudorapidity coverage [ − 1.3 , 1.3 ] . The balance function properly scaled by the width of the observed pseudorapidity window does not depend on the position or size of the pseudorapidity window. This scaling property also holds for particles in different transverse momentum ranges. In addition, we find that the width …


Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani 2010 Old Dominion University

Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani

Physics Faculty Publications

We present a study of high energy photodisintegration of proton-pairs through the γ + 3He → p + p + n channel. Photon energies, , from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. The s−11 scaling of the cross section, as predicted by the constituent counting rule for two nucleon photodisintegration, was observed for the first time. The onset of the scaling is at a higher energy and the cross section is significantly lower than for deuteron (pn pair) photodisintegration. …


Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein 2010 Old Dominion University

Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein

Physics Faculty Publications

We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations …


D Meson Reconstruction At Star Using The Silicon Vertex Tracker (Svt), Sarah Lapointe 2010 Wayne State University

D Meson Reconstruction At Star Using The Silicon Vertex Tracker (Svt), Sarah Lapointe

Wayne State University Dissertations

At the Relativistic Heavy Ion Collider a hot and dense matter is produced in Au+Au collisions at sqrt(sNN) = 200 GeV/c. This matter exhibits features of a new deconfined partonic matter, called the Quark-Gluon Plasma. Charm quarks are expected to be produced predominately from the initial gluon fusion in parton-parton hard scatterings. This indicates that the production of the charm occurs at the early stages of the collision. At this time the system is thought to be partonic, making the charm a powerful probe of the initial conditions. Non-photonic electron measurements in p+p, d+Au, and Au+Au provide some insight of …


Hadron Structure From Holographic Qcd, Zainul Abidin 2010 College of William & Mary - Arts & Sciences

Hadron Structure From Holographic Qcd, Zainul Abidin

Dissertations, Theses, and Masters Projects

The AdS/CFT correspondence relates a strongly coupled gauge theory in four dimensional space-time with a weakly coupled gravity theory in five dimensional space-time. This correspondence provides a way to access the strongly coupled regime of a gauge theory via a perturbative approach in its gravity dual theory. In this dissertation, the gravity dual of Quantum Chromodynamics (QCD) is discussed. The so-called bottom-up approach (AdS/QCD) successfully reproduces the low energy observables at 10-20% accuracy.;An AdS/QCD model with two flavors of quarks is considered, assuming isospin symmetry. Pions and rho mesons masses and decay constants are obtained. We calculate the stress tensor, …


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