Nuclear Commons^™

Simulations Of Electron Detection Systematic Errors For A Ucna+ Experiment, Rashika Gupta

Theses and Dissertations--Physics and Astronomy

The Ultracold Neutron Asymmetry+ (UCNA+) experiment at the Los Alamos Neu- tron Science Center (LANSCE) Ultracold Neutron source is an upgrade of the UCNA experiment, designed to measure the neutron beta decay asymmetry parameter, A 0 , with a precision of less than 0.2% using polarized ultracold neutrons (UCN). Neutron beta decay is governed by the weak interaction, and a precise measurement of A 0 provides a determination of the axial-vector to vector coupling ratio, λ = gA /gV . When combined with a measurement of the neutron lifetime, this allows the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element Vud …

Optimizing External Radioactive Calibration Source Strength To Maximize The Livetime Of The Nexo Detector, Thakur P. Bhatta

Theses and Dissertations--Physics and Astronomy

The proposed next Enriched Xenon Observatory (nEXO) experiment aims to detect neutrinoless double beta decay in 136Xe, a rare process with profound implications for particle physics and our understanding of the neutrino. Achieving the required sensitivity demands ultra-low background conditions, making both material radiop urity screening and precise detector calibration essential. This dissertation addresses two key calibration challenges in preparation for nEXO. First, I investigated discrepancies in calibration efficiency measurements of the high-purity germanium (HPGe) detector named as GeIV located 4850 feet under ground at the Sanford Underground Research Facility, Lead, SD. The root cause for the discrepancy was found …

Static And Dynamic Properties Of Atomic Nuclei With High-Resolution Potentials, Alex Gnech, Alessandro Lovato, Noemi Rocco

Physics Faculty Publications

We compute ground-state and dynamical properties of 4He and 16O nuclei using as input high-resolution, phenomenological nucleon-nucleon and three-nucleon forces that are local in coordinate space. The nuclear Schrödinger equation for both nuclei is accurately solved employing the auxiliary-field diffusion Monte Carlo approach. For the 4He nucleus, detailed benchmarks are carried out with the hyperspherical harmonics method. In addition to presenting results for the binding energies and radii, we also analyze the momentum distributions of these nuclei and their Euclidean response function corresponding to the isoscalar density transition. The latter quantity is particularly relevant for lepton-nucleus scattering experiments, as it …

Dihadron Aziumuthal Correlations In Deep-Inelastic Scattering Off Nuclear Targets, S. J. Paul, S. Morán, M. Arratia, W. K. Brooks, H. Hakobyan, A. El Alaoui, P. Achenbach, J. S. Alvarado, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondí, W. A. Booth, F. Bossu, S. Boiarinov, K. -Th. Brinkmann, W. J. Briscoe, S. Bueltmann, V. D. Burkert, T. Cao, R. Capobianco, D. S. Carman, P. Chatagnon, G. Ciullo, P. L. Cole, M. Contalbrigo, A. D'Angelo, N. Dashyan, R. De Vita, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupre, L. El Fassi, L. Elouadrhiri, P. Eugenio, A. Filippi, C. Fogler, G. Gavalian, G. P. Gilfoyle, D. I. Glazier, A. A. Golubenko, R. W. Gothe, M. Guidal, K. Hafidi, M. Hattawy, F. Hauenstein, D. Heddle, A. Hobart, M. Holtrop, Y. Iiieva, D. G. Ireland, E. L. Isupov, D. Jenkins, H. Jiang, H. S. Jo, K. Joo, T. Kageya, M. Khandaker, A. Kim, W. Kim, V. Klimenko, V. Kubarovsky, S. E. Kuhn, L. Lanza, P. Lenisa, K. Livingston, I. J.D. Macgregor, D. Marchand, V. Mascagna, D. Matamoros, B. Mckinnon, S. Migliorati, T. Mineeva, M. Mirazita, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, K. Neupane, S. Niccolai, G. Niculescu, M. Osipenko, A. I. Ostrovidov, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, W. Phelps, N. Pilleux, M. Pokhrel, S. Polcher Rafael, J. W. Price, Y. Prok, T. Reed, J. Richards, M. Ripani, G. Rosner, P. Rossi, C. Salgado, A. Schmidt, M. B. C. Scott, Y. G. Sharabian, E. V. Shirokov, U. Shrestha, N. Sparveris, M. Spreafico, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, V. Tommaso, E. Voutier, D. P. Watts, X. Wei, R. Williams, M. H. Wood, L. Xu, N. Zachariou, M. Zurek

Physics Faculty Publications

We measured the nuclear dependence of the di-pion azimuthal correlation function in deep-inelastic scattering (DIS) using the CEBAF Large Acceptance Spectrometer and a 5 GeV electron beam. As the nuclear-target size increases, transitioning from deuterium to carbon, iron, and lead, the correlation function broadens monotonically. Its shape exhibits a significant dependence on kinematics, including the transverse momentum of the pions and the difference in their rapidity. None of the various Monte Carlo event generators we evaluated could fully replicate the observed correlation functions and nuclear effects throughout the entire phase space. As the first study of its kind in DIS …

Photoproduction Of The Σ⁺ Hyperon Using Linearly Polarized Photons With Clas, L. Clark, B. Mckinnon, D. G. Ireland, D. I. Glazier, K. Livingston, D. Rönchen, A. G. Acar, P. Achenbach, J. S. Alvarado, M. J. Amaryan, W. R. Armstrong, H. Atac, L. Baashen, L. Barion, M. Battaglieri, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, W. A. Booth, F. Bossù, K. Th. Brinkmann, W. J. Briscoe, W. K. Brooks, S. Bueltmann, T. Cao, R. Capobianco, D. S. Carman, A. Celentano, P. Chatagnon, G. Ciullo, P. L. Cole, M. Contalbrigo, A. D' Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Djalali, M. Dugger, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, P. Eugenio, S. Fegan, R. F. Ferguson, A. Filippi, C. Fogler, K. Gates, G. Gavalian, G. P. Gilfoyle, A. A. Golubenko, R. W. Gothe, M. Guidal, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, E. L. Isupov, D. Jenkins, H. Jiang, H. S. Jo, D. Keller, M. Khandaker, W. Kim, F. J. Klein, V. Klimenko, A. Kripko, V. Kubarovsky, L. Lanza, P. Lenisa, X. Li, I. J. D. Macgregor, D. Marchand, V. Mascagna, D. Matamoros, S. Migliorati, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, K. Neupane, S. Niccolai, G. Niculescu, M. Osipenko, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, W. Phelps, N. Pilleux, M. Pokhrel, S. Polcher Rafael, Y. Prok, T. Reed, J. Richards, M. Ripani, B. G. Ritchie, J. Ritman, G. Rosner, C. Salgado, S. Schadmand, A. Schmidt, R. A. Schumacher, Y. G. Sharabian, E. V. Shirokov, U. Shrestha, D. Sokhan, N. Sparveris, M. Spreafico, S. Stepanyan, I. I. Strakovsky, S. Stauch, J. A. Tan, M. Tenorio, N. Trotta, R. Tyson, M. Ungaro, L. Venturelli, H. Voskanyan, E. Voutier, D. P. Watts, X. Wei, R. Williams, L. Xu, N. Zachariou, Z. W. Zhao, M. Zurek

Physics Faculty Publications

Background: Measurements of the polarization observables Σ, P, T, O_x, O_zfor the reaction ^→𝛾p →K⁰_SΣ⁺ using a linearly polarized photon beam of energy 1.1 to 2.1 GeV are reported.

Purpose: The measured data provide information on a channel that has not been studied extensively, but is required for a full coupled-channel analysis in the nucleon resonance region.

Method: Observables have been simultaneously extracted using likelihood sampling with a Markov-Chain Monte Carlo process.

Results: Angular distributions in bins of photon energy E_γ are produced for each polarization observable. T,O_x,and O_{z …}

Avenues For A Number Density Interpretation Of Dihadron Fragmentation Functions, T. Rogers, A. Courtoy

Physics Faculty Publications

In this letter, we reassess the underlying physics of the number sum rule for dihadron fragmentation functions. We will argue that, currently, there are no settled constraints on what constitutes a valid number density interpretation for multihadron fragmentation functions. Imposing overly restrictive criteria might lead to misinterpretating the data. Most importantly, and on the basis of phenomenological analyses, the slightly varying definitions used in previous work are not excluded from possessing legitimate number density interpretations (up to the usual issues with ultraviolet divergences and renormalization), so long as they are paired with appropriate factorization theorems. We advocate for further theoretical …

Flavor Dependence Of Charged Pion Fragmentation Functions, H. Bhatt, P. Bosted, S. Jia, W. Armstrong, D. Dutta, R. Ent, D. Gaskell, E. Kinney, H. Mkrtchyan, S. Ali, R. Ambrose, D. Androić, C. Ayerbe Gayoso, A. Bandari, V. Berdnikov, D. Bhetuwal, D. Biswas, M. Boer, E. Brash, A. Camsonne, M. Cardona, J. P. Chen, J. Chen, M. Chen, E. M. Christy, S. Danagoulian, M. Diefenthaler, S. Covrig, B. Duran, M. Elaasar, C. Elliot, H. Fenker, E. Fuchey, J. O. Hansen, F. Hauenstein, T. Horn, G. M. Huber, M. K. Jones, M. L. Kabir, A. Karki, B. Karki, S. J. D. Kay, C. Keppel, V. Kumar, N. Lashley-Colthirst, W. B. Li, D. Mack, S. Malace, P. Markowitz, M. Mccaughan, E. Mcclellan, D. Meekins, R. Michaels, A. Mkrtchyan, G. Niculescu, I. Niculescu, B. Pandey, S. Park, E. Pooser, B. Sawatzky, G. R. Smith, H. Szumila-Vance, A. S. Tadepalli, V. Tadevosyan, R. Trotta, H. Voskanyan, S. A. Wood, Z. Ye, C. Yero, X. Zheng

Physics Faculty Publications

We have measured the flavor dependence of multiplicities for π⁺ and π⁻ production in semi-inclusive deep-inelastic scattering (SIDIS) on proton and deuteron to explore a possible charge symmetry violation in fragmentation functions. The experiment used an electron beam with energies of 10.2 and 10.6 GeV at Jefferson Lab and the Hall-C spectrometers. The electron kinematics spanned the range 0.3 < x < 0.6, 2 < Q² < 5.5 GeV², and 2.2 < W < 3.2 GeV. The pion fractional momentum range was 0.3 < z < 0.7, and the transverse momentum range was 0 < p_T < 0.25 GeV/c. Assuming factorization and allowing for isospin breaking, the results can be described by two “favored” and two “unfavored” effective low p_T fragmentation functions that are flavor-dependent. We find each pair converges to a common flavor-independent fragmentation function at the highest W, where factorization is most applicable.

Inclusive Studies Of Two- And Three- Nucleon Short-Range Correlations In ³H And ³He, S. Li, S. N. Santiesteban, J. Arrington, R. Cruz-Torres, L. Kurbany, D. Abrams, S. Alsalmi, D. Androic, K. Aniol, T. Averett, C. Ayerbe Gayoso, J. Bane, S. Barcus, J. Barrow, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, D. Bulumulla, A. Camsonne, J. Castellanos, J. Chen, J. -P. Chen, D. Chrisman, M. E. Christy, C. Clarke, S. Covrig, K. Craycraft, D. Day, D. Dutta, E. Fuchey, C. Gal, F. Garibaldi, T. N. Gautam, T. Gogami, J. Gomez, P. Guèye, A. Habarakada, T. J. Hague, J. O. Hansen, F. Hauenstein, W. Henry, D. W. Higinbotham, R. J. Holt, C. E. Hyde, K. Itabashi, M. Kaneta, A. Karki, A. T. Katramatou, C. E. Keppel, M. Khachatryan, V. Khachatryan, P. M. King, I. Korover, T. Kutz, N. Lashley-Colthirst, W. B. Li, H. Liu, N. Liyanage, E. Long, J. Mammei, P. Markowitz, R. E. Mcclellan, F. Meddi, D. Meekins, S. Mey-Tal Beck, R. Michaels, M. Mihovilovič, A. Moyer, S. Nagao, V. Nelbuyin, D. Nguyen, M. Nycz, M. Olson, L. Ou, V. Owen, C. Palatchi, B. Pandey, A. Papadopoulou, S. Park, S. Paul, T. Petkovic, R. Pomatsalyuk, S. Premathilake, V. Punjabi, R. D. Ransome, P. E. Reimer, J. Reinhold, S. Riordan, J. Roche, V. M. Rodriguez, A. Schmidt, B. Schmookler, E. P. Segarra, A. Shahinyan, S. Širca, K. Slifer, P. Solvignon, T. Su, R. Suleiman, H. Szumila-Vance, L. Tang, Y. Tian, W. Tireman, F. Tortorici, Y. Toyama, K. Uehara, G. M. Urciuoli, D. Votaw, J. Williamson, B. Wojtsekhowski, S. Wood, Z. H. Ye, J. Zhang, X. Zheng

Physics Faculty Publications

Inclusive electron scattering at carefully chosen kinematics can isolate scattering from the high-momentum nucleons in short-range correlations (SRCs). SRCs are produced by the hard, short-distance interactions of nucleons in the nucleus, and because the two-nucleon (2N) SRCs arise from the same N-N interaction in all nuclei, the cross section in the SRC-dominated regime is identical up to an overall scaling factor. This scaling behavior has been used to identify SRC dominance and to measure the contribution of SRCs in a wide range of nuclei. We examine this scaling behavior over a range of momentum transfers using new data on ²H, …

First Measurement Of Near-Threshold And Subthreshold J/Ѱ Photoproduction Off Nuclei, J. R. Pybus, L. Ehinger, T. Kolar, B. Devkota, P. Sharp, B. Yu, M. M. Dalton, D. Dutta, H. Gao, O. Hen, E. Piasetzky, S. N. Santiesteban, A. Schmidt, A. Somov, H. Szumila-Vance, S. Adhikari, A. Asaturyan, A. Austregesilo, C. Ayerbe Gayoso, J. Barlow, V. V. Berdnikov, H. D. Bhatt, D. Bhetuwal, T. Black, W. J. Briscoe, G. Chung, P. L. Cole, A. Deur, R. Dotel, H. Egiyan, P. Eugenio, C. Fanelli, L. Gan, A. Gasparian, J. Guo, K. Hernandez, D. W. Higinbotham, P. Hurck, I. Jaegle, R. T. Jones, V. Kakoyan, A. Karki, H. Li, W. B. Li, G. R. Linera, V. Lyubovitskij, H. Marukyan, M. D. Mccaughan, M. Mccracken, K. Mizutani, D. Nguyen, S. Oresic, A. I. Ostrovidov, Z. Papandreou, C. Paudel, K. Peters, J. Ritman, A. Schick, J. Schwiening, A. Smith, S. Somov, I. Strakovsky, K. Suresh, V. V. Tarasov, S. Taylor, T. Xiao, Z. Zhang, X. Zhou

Physics Faculty Publications

We report on the first measurement of J/ψ photoproduction from nuclei in the photon energy range of 7 to 10.8 GeV, extending above and below the photoproduction threshold in the free proton of ∼8.2 GeV. The experiment used a tagged photon beam incident on deuterium, helium, and carbon, and the GlueX detector at Jefferson Lab to measure the semi-inclusive A(γ,e⁺e^-p) reaction with a dilepton invariant mass M(e⁺e^-)∼m_J/ψ=3.1 GeV. The incoherent J/ψ photoproduction cross sections in the measured nuclei are extracted as a function of the incident photon energy, momentum transfer, …

Inclusive Electron Scattering In The Resonance Region Off A Hydrogen Target With Clas12, V. Klimenko, D. S. Carman, R. W. Gothe, K. Joo, N. Markov, V. I. Mokeev, G. Niculescu, P. Achenbach, J. S. Alvarado, W. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, F. Benmokhtar, A. Bianconi, A. S. Biselli, S. Boiarinov, F. Bossù, K.-Th. Brinkmann, W. J. Briscoe, W. K. Brooks, V. D. Burkert, S. Bueltmann, R. Capobianco, J. Carvajal, A. Celentano, P. Chatagnon, G. Ciullo, A. D'Angelo, N. Dashyan, M. Defurne, R. De Vita, A. Deur, S. Diehl, C. Dilks, C. Djalali, R. Dupré, H. Egiyan, A. El Alaoui, L. El Fassi, L. Elouadrhiri, S. Fegan, I. P. Fernando, A. Filippi, G.. Gavalian, G. P. Gilfoyle, D. I. Glazier, K. Hafidi, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. N. Hiller Blin, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. Jiang, H. S. Jo, S. Joosten, T. Kageya, D. Keller, A. Kim, W. Kim, H. T. Klest, A. Kripko, V. Kubarovsky, S. E. Kuhn, L. Lanza, S. Lee, P. Lenisa, K. Livingston, I. J. D. Macgregor, D. Marchand, D. Martiryan, V. Mascagna, D. Matamoris, B. Mckinnon, T. Mineeva, M. Mirazita, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, S. Niccolai, M. Osipenko, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, W. Phelps, N. Pilleux, S. Polcher Rafael, J. W. Price, Y. Prok, B. A. Raue, J. Richards, M. Ripani, J. Ritman, P. Rossi, A. A. Rusova, C. Salgado, S. Schadmand, A. Schmidt, Y. G. Sharabian, E. V. Shirokov, S. Shrestha, N. Sparveris, M. Spreafico, S. Stepanyan, I. I. Strakovsky, S. Strauch, J. A. Tan, M. Tenorio, N. Trotta, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, T. Vittorini, H. Voskanyan, E. Voutier, D. P. Watts, U. Weerasinghe, X. Wei, M. H. Wood, L. Xu, N. Zachariou, Z. W. Zhao, M. Zurek

Physics Faculty Publications

Inclusive electron scattering cross sections off a hydrogen target at a beam energy of 10.6 GeV have been measured with data collected from the CLAS12 spectrometer at Jefferson Laboratory. These first absolute cross sections from CLAS12 cover a wide kinematic area in invariant mass W of the final state hadrons from the pion threshold up to 2.5 GeV for each bin in virtual photon four-momentum transfer squared Q² from 2.55 to 10.4 GeV² owing to the large scattering angle acceptance of the CLAS12 detector. Comparison of the cross sections with the resonant contributions computed from the CLAS results on the …

Multidimensional Measurements Of Beam Single-Spin Asymmetries In Semi-Inclusive Deep-Inelastic Charged-Kaon Electroproduction Off Protons In The Valence Region, Clas Collaboration, A. Kripko, S. Diehl, K. Joo, P. Achenbach, J. S. Alvarado, M. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, L. Bashkanov, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K. -T. Brinkmann, W. J. Briscoe, W. K. Brooks, T. Cao, R. Capobianco, D. S. Carman, J. C. Carvajal, A. Celentano, P. Chatagnon, G. Ciullo, P. L. Cole, M. Contalbrigo, V. Crede, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, L. Elouadrhiri, S. Fegan, I. P. Fernando, A. Filippi, G. Gavalian, G. P. Gilfoyle, D. I. Glazier, R. W. Gothe, Y. Gotra, K. Hafidi, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. Jiang, H. S. Jo, T. Kageya, A. Kim, W. Kim, V. Klimenko, V. Kubarovsky, S. E. Kuhn, L. Lanza, P. Lenisa, X. Li, Z. Lu, I. J. D. Macgregor, D. Marchand, D. Martiryan, V. Mascagna, D. Matamoros, M. Maynes, B. Mckinnon, R. G. Milner, T. Mineeva, M. Mirazita, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, N. Pilleux, S. Polcher Rafael, J. Poudel, J. W. Price, Y. Prok, T. Reed, M. Ripani, J. Ritman, C. D. Roberts, P. Rossi, A. A. Rusova, S. Schadmand, A. Schmidt, Y. G. Sharabian, E. V. Shirokov, S. Shrestha, U. Shrestha, D. Sokhan, N. Sparveris, M. Spreafico, I. I. Strakovsky, S. Strauch, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, T. Vittorini, H. Voskanyan, A. Vossen, E. Voutier, Y. Wang, D. P. Watts, U. Weerasinghe, X. Wei, M. H. Wood, L. Xu, S. -S. Xu, N. Zachariou, V. Ziegler, M. Zurek

Physics Faculty Publications

Measurements of beam single-spin asymmetries in semi-inclusive deep-inelastic electron scattering (SIDIS) with positively charged kaons off protons have been performed with 10.6 and 10.2 GeV incident electron beams using the CLAS12 spectrometer at Jefferson Lab. We report an analysis of the electroproduction of positively charged kaons over a large kinematic range of fractional energy, Bjorken x, transverse momentum, and photon virtualities Q² ranging from 1 GeV² up to 6 GeV². This is the first published multidimensionally binned CLAS12 measurement of a kaon SIDIS single-spin asymmetry in the valence quark regime. The data provide constraints on the structure function ratio …

Vaim-Cff: A Variational Autoencoder Inverse Mapper Solution To Compton Form Factor Extraction From Deeply Virtual Compton Scattering, Manal Almaeen, Tareq Alghamdi, Brandon Kriesten, Douglas Adams, Yaohang Li, Huey-Wen Lin, Simonetta Liuti

Computer Science Faculty Publications

We develop a new methodology for extracting Compton form factors (CFFs) from deeply virtual exclusive reactions such as the unpolarized DVCS cross section using a specialized inverse problem solver, a variational autoencoder inverse mapper (VAIM). The VAIM-CFF framework not only allows us access to a fitted solution set possibly containing multiple solutions in the extraction of all 8 CFFs from a single cross section measurement, but also accesses the lost information contained in the forward mapping from CFFs to cross section. We investigate various assumptions and their effects on the predicted CFFs such as cross section organization, number of extracted …

Ai For Nuclear Physics: The Exclaim Project, S. Liuti, D. Adams, M. Boër, G. W. Chern, M. Cuic, M. Engelhardt, G. R. Goldstein, B. Kriesten, Y. Li, H. W. Lin, M. Sievert, D. Sivers

Computer Science Faculty Publications

An overview of the recent activity of the newly funded EXCLusives with AI and Machine learning (EXCLAIM) collaboration is presented. The main goal of the collaboration is to develop a framework to implement AI and machine learning techniques in problems emerging from the phenomenology of high energy exclusive scattering processes from nucleons and nuclei, maximizing the information that can be extracted from various sets of experimental data, while implementing theoretical constraints from lattice QCD. A specific perspective embraced by EXCLAIM is to use the methods of theoretical physics to understand the working of ML, beyond its standardized applications to physics …

Effect Of Temperature And Rhenium Content In Precipitates On Dispersion Hardening Of Tungsten, Yulia R. Sharapova, Arseny M. Kazakov, Elena A. Korznikova, Alexandr Zinovev, Dmitry Terentyev, Sergey V. Dmitriev

Karbala International Journal of Modern Science

Tungsten (W) is being developed as a plasma-facing material for fusion reactors, where it is subjected to MeV neutron irradiation, low-energy helium isotope particles, and high temperatures. These conditions lead to the formation of point defects, dislocation loops, voids, and transmutation into rhenium (Re) and osmium (Os), which form precipitates that significantly impact dislocation motion and increase hardness. This study uses molecular dynamics modeling to examine the interaction between an edge dislocation and Re-rich particles of various stoichiometries, specifically coherent bcc-phase particles and noncoherent σ-phase precipitates. Results show that shear stress increases by approximately 20-40% with larger particle size (3-5 …

Gauss-Lobatto Method For Nuclear Reactivity Calculation, Daniel Suescún-Díaz, Luis E. Cardoso-Páez, Diego Peña-Lara

Karbala International Journal of Modern Science

In this paper, we introduce a novel approach to numerical solving for nuclear reactivity using the inverse equation of point kinetics as a model. Our method leverages the Gauss-Lobatto quadrature, incorporating multiple time steps and nodes derived from Legendre polynomials of varying orders. To enhance the accuracy of the differential component of the inverse equation, we employed a differential scheme based on the Gauss-Lobatto quadrature nodes. To address fluctuations in neutron population density, we implemented a second-order low-pass Butterworth filter with a minimal window length of M = 3 samples. Through extensive numerical simulations, we assessed the precision of our …

Fast Neutron & Gamma-Ray Scintillation And Broadband Photoluminescence From Gallium Nitride & Gallium Oxide: Developing Radiation-Hard Diagnostic Platforms, Daniel Jesus Valdes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Integrated scintillation and electronics processing materials are of critical importance in environments exposed to high levels of radiation, such as nuclear fusion diagnostics and space missions. This dissertation focuses on the radiation detection capabilities of gallium oxide (Ga2O3) and gallium nitride (GaN), exploring their responses to fast neutrons and gamma rays. Using high-energy neutron beam facilities at Los Alamos Neutron Science Center (LANSCE) Flight Path 4FP60R, we exposed both Ga2O3 and GaN crystals to neutron irradiation spanning an energy spectrum ranging from 1 to 400 MeV. A Pi-Max 4 fast-gated Intensified CCD (ICCD) camera captured the transient scintillation responses for …

Simulations, Modeling And Data Analysis Of Parity Violating Electron Scattering Experiments, Yufan Chen

Doctoral Dissertations

In the Standard Model (SM) of nuclear and particle physics, parity violation is incorporated through the representation of the weak interaction as a chiral gauge interaction. Only the left-handed components of particles and right-handed components of antiparticles participate in weak interactions in the Standard Model. This implies that parity is asymmetric for the weak interaction. Parity violating electron scattering (PVES) experiments are designed to probe the physics parameters related to the SM, with the possibility to discover physics beyond the SM (BSM) by measuring the parity violating asymmetry 𝐴𝑃𝑉 of longitudinally polarized electrons scattered off unpolarized targets with high precision. …

Constraining Accreted Neutron Star Crust Shallow Heating With The Inferred Depth Of Carbon Ignition In X-Ray Superbursts, Zachary P. Meisel

Faculty Publications

Evidence has accumulated for an as-yet unaccounted for source of heat located at shallow depths within the accreted neutron star crust. However, the nature of this heat source is unknown. I demonstrate that the inferred depth of carbon ignition in X-ray superbursts can be used as an additional constraint for the magnitude and depth of shallow heating. The inferred shallow heating properties are relatively insensitive to the assumed crust composition and carbon fusion reaction rate. For low-accretion rates, the results are weakly dependent on the duration of the accretion outburst, so long as accretion has ensued for enough time to …

Broken Su(3) Description Of Energy Levels And Decay Properties In Gadolinium Isotopes (A=156-160), Fahmi Sh. Radhi, Amir Abdul Ameer Mohammed Ali Dr., Ali H. Al-Musawi

Karbala International Journal of Modern Science

This study presents an in-depth examination of the energy levels and decay properties of Gadolinium (Gd) isotopes with mass numbers (A=156-160), utilizing the Interacting Boson Model-1 (IBM-1) within a broken SU(3) symmetry framework. Through this approach, we systematically calculated and analyzed the energy spectra, B(E2) transition probabilities, quadrupole moments, and potential energy surface (PES) which provided valuable insights into the shape and collective behavior of nuclei, as well as the decay properties of the selected Gd isotopes. The broken SU(3) symmetries provide a good description to the isotopes under study. This comprehensive analysis enhances the understanding of the nuclear structure …

Measuring Clas12 D(E, E′Π±) Cross Sections For E4nu, Caleb Fogler

Physics Theses & Dissertations

Neutrino experiments need neutrino event generators such as GENIE to simulate neutrino-nucleus (νA) interactions in order to measure neutrino oscillations. We need eA data to validate GENIE. GENIE d(e, e′ ) cross sections do not match data in the pion production region. Further analysis of this region can help constrain GENIE models. The goal of this project was to compare 4.244 GeV CLAS12 d(e, e′π±) cross sections to GENIE predictions. We analyzed data from the Fall 2019 run period of Run Group B (RG-B). We applied particle identification, fiducial, and vertex …