Physics Commons^™

Spontaneous Symmetry Breaking And Goldstone Theorem, Emilia Szymańska

2023 REYES Proceedings

We discuss the concept of spontaneous symmetry breaking and illustrate it with a general example. We consider Wigner-Weyl and Nambu-Goldstone realisations of symmetry in the quantum theory. Next, we state Goldstone’s theorem and sketch its proof. We discuss why quantum chromodynamics is not realised in the Wigner-Weyl mode. We also consider different order parameters of spontaneous chiral symmetry breaking.

Ml-Based Surrogates And Emulators, Tareq Alghamdi, Yaohang Li, Nobuo Sato

College of Sciences Posters

No abstract provided.

True Random Number Generators, Jade Geng

Senior Projects Spring 2023

Quantum Random Number Generators(QRNGs), or True Random Number Generators, generate random numbers based on naturally unpredictable(or hard-to-predict) sources. Their unpredictability results in a broad application in cryptography and technology. Their sources range from nuclear decay gamma rays to cosmic rays, then to quantum optics. This thesis aims to explore various randomness sources and compare their efficiency by running a series of randomness tests. The specific setup for each random number generator will also be presented.

Nudyclr: Nuclear Dynamic Co-Learned Representations, Víctor Samuel Pérez-Díaz

2023 REYES Proceedings

NuCLR (Nuclear Co-Learned Representations) is a cutting-edge multi-task deep learning framework designed to predict essential nuclear observables, including binding energies, decay energies, and nuclear charge radii. As part of the REYES Mentorship Program, we investigated the application of dynamic loss weighting to further refine NuCLR’s predictive performance. Our findings indicate that while weighting strategies can enhance accuracy in specific tasks, such as binding energy prediction, they may underperform in others. Equal Weighting (EW), the original method employed by NuCLR, demonstrated consistent performance across multiple tasks, affirming its robustness. This report succinctly presents the developments and results of the mentorship program …

Resonance Signatures In 𝜋+𝜋− Scattering: Theoretical Analysis And Interpretation, Mayul Verma

2023 REYES Proceedings

Hadron colour confinement, a phenomenon central to Quantum Chromodynamics (QCD), presents a formidable challenge in theoretical physics. The non-perturbative nature of confinement necessitates innovative approaches to the production of and reaction mechanisms between these subatomic particles. In the pursuit of comprehending the fundamental constituents of matter, particle resonances assume a pivotal role. Through the utilization of advanced methodologies like 𝑆-Matrix formulations, more profound insights into resonance phenomena and their effects on the dynamics of particle interactions can be attained. This research paper embarks on a mathematical journey that holds the potential to shed light on the intricate structure of particle …

Design Of The Highly Uniform Magnetic Field And Spin-Transport Magnetic Field Coils For The Los Alamos National Lab Neutron Electric Dipole Moment Experiment, Jared Brewington

Theses and Dissertations--Physics and Astronomy

Charge-Parity (CP) violation is one of Sakharov's three conditions which serve as guidelines for the generation of a matter-antimatter asymmetry in the early universe. The Standard Model (SM) of particle physics contains sources of CP violation which can be used to predict the baryon asymmetry. The observed baryon asymmetry is not predicted from SM calculations, meaning there must be additional sources of CP violation beyond the Standard Model (BSM) to generate the asymmetry. Permanent electric dipole moments (EDMs), which are inherently parity- and time reversal- violating, present a promising avenue for the discovery of new sources of CP violation to …

The Design Of Primary Holding Magnet For The Lanl Neutron Electric Dipole Moment Experiment, Piya Amara Palamure

Theses and Dissertations--Physics and Astronomy

The measurement of the permanent electric dipole moment of the neutron (nEDM) plays a significant role in searching for sources of beyond standard model CP violating physics. The goal of the Los Alamos National Laboratory (LANL) nEDM experiment is to push the upper limit of the nEDM to < 3 × 10−27 e·cm (68 % CL). A highly uniform magnetic field is key to achieving this sensitivity for the nEDM measurement by reducing the systematic uncertainties associated with the magnetic field non-uniformity. The B0 coil was designed to achieve a field uniformity of < 0.3 nT·m−1 at a nominal holding field of 1 µT. This document will outline a novel technique employed in the construction of the B0 coil using printed circuit boards (PCBs) and will present preliminary field maps obtained with the B0 coil housed in a magnetically shielded room (MSR) at LANL.

As Ultra Cold Neutrons (UCNs) move from the source to the measurement cells, the UCNs experience a large magnetic field gradient in the region between the layers of the MSR. This large gradient would otherwise cause depolarization of the UCNs. To mitigate this, a double cos θ coil will serve as the …

Determining Deuterium Polarization Via Nuclear Magnetic Resonance, Nicholas Muche

Honors Theses and Capstones

Dynamic Nuclear Polarization (DNP) is a method by which the spins of electrons are specifically targeted by microwaves at resonance frequency in order to induce spin flips. Occasionally, the electron spins couple with nuclear spins and nuclear spin flips are induced. The relaxation time of the electron is significantly lower than that of the nuclei, which allows for large polarization. The main goal of the Slifer Lab is to utilize specifically prepared crystalline structures in order to separate the convoluted energy transitions ("Batman Peak") in the deuterium's nuclear magnetic resonance (NMR) signal, which would allow for tensor enhancement of deuterium. …

Particle Swarm Optimization For High Rigidity Spectrometer, Yicheng Wang

Honors Theses

The goal of this project is to find reliable parameter settings for a multi-dimensional global optimizer to optimize the performance of a large acceptance ion optical system for the requirements of nuclear physics experiments. We develop and test the Particle Swarm Optimization (PSO), a global optimization algorithm designed for continuous multi-dimensional problems, on a large acceptance particle beam separator, the High Rigidity Spectrometer (HRS) at the Facility for Rare Isotope Beams (FRIB), which is a laboratory specializing in the production and experimental study of short-lived nuclear matter. We split the HRS into two sections, the High-Transmission Beamline (HTBL) and the …

A Multidimensional Study Of The Structure Function Ratio Σlt'/ Σ₀ From Hard Exclusive ��⁺ Electro-Production Off Protons In The Gpd Regime, S. Diehl, A. Kim, K. Joo, P. Achenbach, Z. Akbar, M. J. Amaryan, H. Atac, H. Avagyan, C. Ayerbe Gayoso, L. Baashen, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinsky, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, W.A. Booth, M. Zurek, Et Al.

Physics Faculty Publications

A multidimensional extraction of the structure function ratio from the hard exclusive ^→ep → e'n��+ reaction above the resonance region has been performed. The study was done based on beam-spin asymmetry measurements using a 10.6 GeV incident electron beam on a liquid-hydrogen target and the CLAS12 spectrometer at Jefferson Lab. The measurements focus on the very forward regime (t/Q²≪ 1) with a wide kinematic range of in the valence regime (0.17 < ��_B < 0.55), and virtualities ranging from 1.5 GeV² up to 6 GeV². The results and their comparison to theoretical models based on Generalized Parton Distributions demonstrate the sensitivity to chiral-odd …

Exclusive 𝝅⁻ Electroproduction Off The Neutron In Deuterium In The Resonance Region, Y. Tian, R. W. Gothe, V. I. Mokeev, G. Hollis, M. J. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. Biselli, F. Bossù, S. Boiarinov, M. Bondì, J. Zhang, Et Al., The Clas Collaboration

Physics Faculty Publications

New results for the exclusive and quasifree cross sections off neutrons bound in deuterium 𝛾_vn(p) → pπ− (p) are presented over a wide final state hadron angle range with a kinematic coverage of the invariant mass (W) up to 1.825 GeV and the four-momentum transfer squared (Q²) from 0.4 to 1.0 GeV². The exclusive structure functions were extracted and their Legendre moments were obtained. Final-state-interaction contributions have been kinematically separated from the extracted quasifree cross sections off bound neutrons solely based on the analysis of the experimental data. These new results will serve as …

Observation Of Large Missing-Momentum (E, E' P) Cross-Section Scaling And The Onset Of Correlated-Pair Dominance In Nuclei, I. Korover, A. W. Denniston, A. Kiral, A. Schmidt, A. Lovato, N. Rocco, A. Nikolakopoulos, L. B. Weinstein, E. Piasetzky, O. Hen, M. J. Amaryan, Giovanni Angelini, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, Fatiha Benmokhtar, A. Bianconi, Z. W. Zhao, Et Al., Clas Collaboration

Physics Faculty Publications

We report the measurement of 𝒙_B scaling in (e,e′p) cross-section ratios off nuclei relative to deuterium at large missing momentum of 350 ≤ _Pmiss ≤ 600 MeV/c. The observed scaling extends over a kinematic range of 0.7 ≤ 𝒙_B ≤ 1.8, which is significantly wider than 1.4 ≤ 𝒙_B ≤ 1.8 previously observed for inclusive (e,e′) cross-section ratios. The 𝒙_B-integrated cross-section ratios become constant (i.e., scale) beginning at p_miss ≈ kF, the nuclear Fermi momentum. Comparing with theoretical calculations we find good agreement with generalized contact formalism calculations for high missing …

Observation Of Correlations Between Spin And Transverse Momenta In Back-To-Back Dihadron Production At Clas12, H. Avakian, T.B. Hayward, A. Kotzinian, W.R. Armstrong, H. Atac, C. Ayerbe Gayoso, L. Baashen, N.A. Balzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, S. Boiarinov, M. Zurek, Et Al.

Physics Faculty Publications

We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e'pπ⁺ X events, where Δϕ is the difference …

Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Ŝirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang

Physics Faculty Publications

The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,e′p) cross section in parallel kinematics using a natural titanium target. In this paper, we report the analysis of the dataset obtained in different kinematics for our solid natural titanium target. Data were obtained in a range of missing momentum and missing energy between 15 ≲ p_m ≲ 250  MeV/c and 12 ≲ Em ≲ 80  MeV, respectively, and using an electron beam energy of 2.2 GeV. We measured the reduced cross section with ∼7% accuracy as a function of both missing momentum and missing energy. …

Identification Of Identical Bands And Energy Staggering Phenomena In Superdeformed Nuclei In A=190 Mass Region In The Framework Of A Novel Proposed Simple Formula, Farid.A. Elmanakely, Gamal.S.M. Ahmed, Shimaa Abdelfattah, Ali. M. Khalaf

Al-Azhar Bulletin of Science

A total of eleven superdeformed rotational bands (SDRB’s) in the A=190 mass zone were described in the framework of a novel proposed simple phenomenological rotational formula as outcome of collective model. The proposed model contains the original pure rotation limit AI (I+1) plus perturbation term proportionate to the cubic power of the spin I. The bandhead spins and the model parameters were selected by a best fit method, utilizing a computerized search program to obtain best match between experimental and calculated transition energies. The spin propositions are mostly consistent with the findings of earlier works. The calculated gamma-ray transition energies …

Measurement Of The Helicity Asymmetry E For The 𝛾p → P𝛑⁰ Reaction In The Resonance Region, C. W. Kim, N. Zachariou, M. Bashkanov, W. J. Briscoe, S. Fegan, V. L. Kashevarov, K. Nikonov, A. Sarantsev, A. Schmidt, I. I. Strakovsky, D. P. Watts, R. L. Workman, P. Achenbach, Z. Akbar, M. J. Amaryan, G. Angelini, W. R. Armstrong, H. Atac, L. Baashen, M. Zurek, Et Al., The Clas Collaboration

Physics Faculty Publications

The double-spin-polarization observable E for 𝛾^→ p^→ → p𝛑⁰ has been measured with the CEBAF Large Acceptance Spectrometer (CLAS) at photon beam energies E𝛾 from 0.367 to 2.173 GeV (corresponding to center-of-mass energies from 1.240 to 2.200 GeV) for pion center-of-mass angles, cos θ^c.m._𝛑⁰, between - 0.86 and 0.82. These new CLAS measurements cover a broader energy range and have smaller uncertainties compared to previous CBELSA data and provide an important independent check on systematics. These measurements are compared to predictions as well as new global fits from The George Washington University, Mainz, and Bonn-Gatchina …

Measurement Of Spin-Density Matrix Elements In P(770) Production With A Linearly Polarized Photon Beam At E𝛾 = 8.2-8.8 Gev, S. Adhikari, F. Afzal, C. S. Akondi, M. Albrecht, M. Amaryan, V. Arroyave, A. Asaturyan, A. Austregesilo, Z. Baldwin, F. Barbosa, J. Barlow, E. Barriga, R. Barsotti, T. D. Beattie, V. V. Berdnikov, T. Black, W. Boeglin, W. J. Briscoe, T. Britton, B. Zihlmann, Et Al., Gluex Collaboration

Physics Faculty Publications

The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized 8.5 GeV photons impinging on a hydrogen target which is contained within a detector with near-complete coverage for charged and neutral particles. We present measurements of spin-density matrix elements for the photoproduction of the vector meson ρ(770). The statistical precision achieved exceeds that of previous experiments for polarized photoproduction in this energy range by orders of magnitude. We confirm a high degree of s-channel helicity conservation at small squared four-momentum transfer t and are able to extract the t dependence of natural- and unnatural-parity exchange contributions to …

Liouvillian Dynamics Of The Open Schwinger Model: String Breaking And Kinetic Dissipation In A Thermal Medium, Kyle Lee, James Mulligan, Felix Ringer, Xiaojun Yao

Physics Faculty Publications

Understanding the dynamics of bound state formation is one of the fundamental questions in confining quantum field theories such as Quantum Chromodynamics (QCD). One hadronization mechanism that has garnered significant attention is the breaking of a string initially connecting a fermion and an antifermion. Deepening our understanding of real-time string-breaking dynamics with simpler, lower dimensional models like the Schwinger model can improve our understanding of the hadronization process in QCD and other confining systems found in condensed matter and statistical systems. In this paper, we consider the string-breaking dynamics within the Schwinger model and investigate its modification inside a thermal …

Prospects For 𝛾*𝛾* → 𝜋𝜋 Via Lattice Qcd, Raúl Briceño, Andrew W. Jackura, Arkaitz Rodas, Juan V. Guerrero

Physics Faculty Publications

The 𝛾*𝛾* → 𝜋𝜋 scattering amplitude plays a key role in a wide range of phenomena, including understanding the inner structure of scalar resonances as well as constraining the hadronic contributions to the anomalous magnetic moment of the muon. In this work, we explain how the infinite-volume Minkowski amplitude can be constrained from finite-volume Euclidean correlation functions. The relationship between the finite-volume Euclidean correlation functions and the desired amplitude holds up to energies where 3𝜋 states can go on shell, and is exact up to exponentially small corrections that scale like 𝒪(e^−m𝜋L), where L is the spatial extent …

Generation And Characterization Of Magnetized Electron Beam From A Dc High Voltage Photogun For Electron Beam Cooling Application, S.A.K. Wijethunga, M. A. Mamun, R. Suleiman, P. Adderley, B. Bullard, J. Benesch, Jean R. Delayen, J. Grames, C. Hernandez-Garcia, F. Hannon, Geoffrey A. Krafft, G. Palacios-Serrano, M. Poelker, M. Stefani, Y. Wang, S. Zhang

Physics Faculty Publications

One of the most challenging requirements for the proposed Electron–Ion Collider is the strong cooling of the proton beam, which is key to achieving the collider’s desired luminosity of order 10³³–10³⁴cm⁻²s⁻¹. Magnetized bunched-beam electron cooling could be a means to achieve the required high luminosity, where strong cooling is accomplished inside a cooling solenoid where the ions co-propagate with an electron beam generated from a source immersed in a magnetic field. To increase the cooling efficiency, a bunched electron beam with high bunch charge and high repetition rate is required. This work …

First Measurement Of Λ Electroproduction Off Nuclei In The Current And Target Fragmentation Regions, T. Chetry, L. El Fassi, W. K. Brooks, R. Dupré, A. El Alaoui, K. Hafidi, P. Achenbach, K. P. Adhikari, Z. Akbar, W.R. Armstrong, M. Arratia, H. Atac, H. Avakian, L. Baashen, N.A. Baltzell, M. Bashkanov, M. Battaglieri, I. Bedlinsky, B. Benkel, M. Zurek, Et Al., Clas Collaboration

Physics Faculty Publications

We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high zand an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This …

Basics Of Factorization In A Scalar Yukawa Field Theory, F. Aslan, L. Gamberg, J.O. Gonzalez-Hernandez, T. Rainaldi, T. C. Rogers

Physics Faculty Publications

The factorization theorems of QCD apply equally well to most simple quantum field theories that require renormalization but where direct calculations are much more straightforward. Working with these simpler theories is convenient for stress testing the limits of the factorization program and for examining general properties of the parton density functions or other correlation functions that might be necessary for a factorized description of a process. With this view in mind, we review the steps of factorization in a real scalar Yukawa field theory for both deep inelastic scattering and semi-inclusive deep inelastic scattering cross sections. In the case of …

Electron Scattering And Neutrino Physics, A. M. Ankowski, A. Ashkenazi, S. Bacca, J. L. Barrow, M. Betancourt, A. Bodek, M. E. Christy, L. Doria, S. Dytman, A. Friedland, O. Hen, C. J. Horowitz, N. Jachowicz, W. Ketchum, T. Lux, K. Mahn, C. Mariani, J. Newby, V. Pandey, A. Papadopoulou, E. Radicioni, F. Sánchez, C. Sfienti, J. M. Udías, L. Weinstein, L. Alvarez-Ruso, J. E. Amaro, C. A. Argüelles, A. B. Balantekin, S. Bolognesi, V. Brdar, P. Butti, S. Carey, Z. Djurcic, O. Dvornikov, S. Edayath, S. Gardiner, J. Isaacson, W. Jay, K. S. Mcfarland, A. Nikolakopoulos, A. Norrick, S. Pastore, G. Paz, M. H. Reno, I. Ruiz Simo, J. E. Sobczyk, A. Sousa, N. Toro, Y. D. Tsai, M. Wagman, J. G. Walsh, G. Yang

Physics Faculty Publications

A thorough understanding of neutrino–nucleus scattering physics is crucial for the successful execution of the entire US neutrino physics program. Neutrino–nucleus interaction constitutes one of the biggest systematic uncertainties in neutrino experiments—both at intermediate energies affecting long-baseline deep underground neutrino experiment, as well as at low energies affecting coherent scattering neutrino program—and could well be the difference between achieving or missing discovery level precision. To this end, electron–nucleus scattering experiments provide vital information to test, assess and validate different nuclear models and event generators intended to test, assess and validate different nuclear models and event generators intended to be used …

Nuclear Magnetic Quadrupole Moment Of ¹⁷⁵Lu And Parity-Violating Polarization Degree Of Levels In ¹⁷⁵Luoh⁺, Igor Kurchavov, Daniel Maison, Leonid Skripnikov, Matt Grau, Alexander Petrov

Physics Faculty Publications

A calculation is performed of the parity-violating polarizations in the external electric field, which are associated with the electron electric dipole moment (eEDM) and magnetic quadrupole moment (MQM) of the ¹⁷⁵Lu nucleus, as well as the determination of the rovibrational structure for the ¹⁷⁵LuOH⁺ cation. Beyond the bending of the molecule, the slight effect of the stretching of the distance between Lu and OH is taken into account. This study is required for the preparation of the experiment and for the extraction of the eEDM and MQM values of ¹⁷⁵Lu from future measurements.

Parton Distribution Functions For Pseudoscalar Mesons In The Confining Effective Chiral Quark Theory, Parada Tobel Paraduan Hutauruk, Seung-Il Nam

Makara Journal of Science

This review paper presents the gluon, sea, and valence quark distributions of the pseudoscalar (PS) mesons. The calculations of the parton structure of PS mesons are performed using the Bethe-Salpeter equation—Nambu-Jona-Lasinio (BSE-NJL) model, which offers a clear description of the dynamical chiral symmetry breaking (D SB) of the low-energy non-perturbative quantum chromodynamics (QCD), with the help of the Schwinger proper-time regularization scheme that simulates the color QCD confinement. Our results for the dynamical quark mass—which emerged from the spontaneous chiral symmetry breaking (S SB)—are generated via the chiral condensate in the chiral limit and beyond. Results for the valence parton …

The Effect Of Ionization Density In Applications Of Radiation Detection, Dosimetry, And Therapy, Daniel Mulrow

Arts & Sciences Electronic Theses and Dissertations

This dissertation covers a wide range of topics but is linked by the common theme of radiation interacting with materials and studying the result of those interactions. The introduction describes the fundamentals of how radiation interacts with material and how we are able to detect that radiation and the application of how we use those interactions in radiation oncology. The thesis starts with a chapter detailing the temperature dependence of the photophysics in two organic scintillators. This chapter is the foundation for a future study that will look the degree to which these scintillators can distinguish between gammas and neutrons …

Nuclear Power Plant In Las Vegas, Ryan W. Murray

Undergraduate Research Symposium Posters

This research focuses on the impact of a “Nuclear Power Plant in Las Vegas” or ‘NPP in LV’ for short. Nuclear power is clean, has no greenhouse gas emissions, and has a moderate cost of kilowatt hours. Las Vegas, or more specifically Clark County uses Gas power plants to produce a majority of their electricity. My project will show what a nuclear plant could do if built in the city of Las Vegas. What is a Nuclear power plant? The EIA’s definition is “A nuclear power plant uses the heat that a nuclear reactor produces to turn water into steam, …

Precise Measurement Of The Nuclear Dependence Of The Emc Effect In Light Nuclei, Abishek Karki, Abishek Karki

Theses and Dissertations

Measurements of inclusive electron scattering cross-section ratios from light nuclei over a wide range of the Björken �� (0.3 < �� < 1) up to �� 2 = 8.3 GeV² were made as part of experiment E10-10-008, which was conducted in Hall C at the Thomas Jefferson National Accelerator Facility. The measurements were performed using a beam energy of 10.602 GeV and an average beam current of 45 ��A. This dissertation provides a thorough description of the experiment as well as the extracted ratios of inclusive nuclear cross-sections with respect to the deuterium cross-sections (the EMC effect) for the targets ⁹ Be, ¹² C, ¹⁰ B, and ¹¹ B. The …

Development Of A New High-Resolution Neutron Detector And Beta-Delayed Neutron Spectroscopy Of 24o., Shree K. Neupane

Doctoral Dissertations

An efficient neutron detection system with good energy resolution is needed to correctly characterize the decays of neutron-rich nuclei where beta-delayed neutron emission is a dominant decay mode. Precision neutron spectroscopy probes nuclear structure effects in neutron-rich nuclei and is essential to exploit the opportunities in new-generation radioactive beam facilities. A new high-resolution neutron detector, Neutron dEtector with Xn Tracking (NEXT), has been constructed, characterized, and tested in decay and reaction experiments. Its essential capability is the neutron interaction position localization, which enables improvement in energy resolution without compromising detection efficiency in the time-of-flight measurements. Neutron-gamma discrimination capability of NEXT …

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Constraining The 30p(P,Γ)31s Reaction Using 30p(D,Pγ)31p With Goddess, Rajesh Ghimire

Doctoral Dissertations

The ³⁰P(p,γ)³¹S reaction acts as a bottleneck for classical nova nucleosynthesis beyond A=30 in ONe novae, due in part to the long lifetime of ³⁰P (∼2.5 minutes) with respect to the timescale of a nova outburst. Also, the ³⁰P(p,γ)³¹S reaction rate directly affects the isotopic ratio of ³⁰Si/²⁸Si, which is an important nova identifier in the analysis of pre-solar grains. O/S, S/Al, O/P, and P/Al elemental abundance ratios can be used as nuclear thermometers for classical novae by constraining the ³⁰P(p,γ)³¹S reaction rate.

However, direct measurement of …