Nuclear Commons^™

Deep Virtual Pion Pair Production, Dilini Lakshani Bulumulla

Physics Theses & Dissertations

This experiment investigates the deep virtual production of both σ− and ρ− mesons, with a particular focus on the microscopic structure of the σ mesons. While the ρ meson is an ordinary qq¯ pair, the σ meson is composed of not only the typical qq¯ pair, making it a topic of controversy for nearly six decades. Although the existence of the σ− meson is now well established, its microscopic structure remains poorly understood. The primary objective of this thesis is to contribute to the understanding of the σ meson by analyzing its deep virtual production. The main focus of this …

Gamma-Ray Spectroscopy Of One-Neutron Knockout From 72se, Alyssa Himmelreich

Physics and Astronomy Summer Fellows

We studied single-neuron excitations of the exotic nucleus ⁷¹Se with the one-neutron knockout reaction from a ⁷²Se beam at the National Superconducting Cyclotron Laboratory. We measured gamma rays de-exciting states in ⁷¹Se using the Gretina gamma-ray tracking array and the momentum of the ⁷¹Se reaction product with the S800 Magnetic Spectrograph. We utilize a supercomputer to run multiple simulations and fit them to our gamma-ray spectrum. Using gamma-ray yields and level schemes, we can determine the number of times each excited state was populated by neutron knockout. We deduced cross sections for populating single-neutron excitations of …

A Statistical Framework For Automating Resonance Detection: Modelling Pion Proton Collision Activity, Shahnaz Abdul Hameed

2023 REYES Proceedings

In this paper, we analyze π− − p elastic collision data from the Particle Data Group (PDG), by creating a general framework to study resonance activity: automating peak detection, extrapolating, parametrizing thresholds, filtering resonances and further comparing and extracting characteristics, to identify Delta (Δ) baryons. We then analyse experimental Energy vs Phase-Shift (δ) data for the collision π+ +π− → π− +π+, model the T matrix from a curve fitted polynomial representation of the K⁻¹ matrix, simulate its Riemann sheets and analyse it to identify the characteristics of ρ⁰(770) meson, as well as estimate their uncertainties. …

Fractional Charge Concept Opened Gates For New Ideas On Composition Of Matter, Polievkt Perov

College of Arts & Sciences Faculty Works

Before the concept of quarks with fractional electric charges was introduced, the electron charge magnitude e was considered as the smallest amount of charge in nature so the charge of any object could be only an integer number of ± e. Then it was suggested that the proton and neutrons are composed of quarks with the fractional charges, combined in such a way that the total charge of a proton occurred to be that same known charge +e, and the charge of a neutron was zero. We suggest expanding that fruitful concept of fractional charges to build structural models of …

New Reaction Of Neutron-Proton Conversion, Polievkt Perov

College of Arts & Sciences Faculty Works

Using our models of composite particles as consisting just of two types of elementary basic charges, +e/3 and -e/3, we suggest that in any nuclear reaction the total numbers of basic charges of each of the two types are conserved. That means that in any nuclear reaction, the basic elementary charges present in the reactants can join in different combinations to form the products of the reaction. This is like a balanced chemical equation where the number of atoms of each element is conserved. We apply this suggested principle of conservation of basic elementary charges in any nuclear reaction to …

Measurement Of The Β-Decay Properties Of A=105 Isotopes Using The Modular Total Absorption Spectrometer And The Development Of The Beta Spectrum Module, Thomas J. Ruland

LSU Doctoral Dissertations

Nuclear reactors produce an extremely diverse population of beta-decaying isotopes. Accurate and precise knowledge of the beta-decay properties of these isotopes is vital to safe reactor operations as well as informing next-generation reactor design. These beta-decay properties not only impact the design and operation of nuclear reactors, but they influence the expected antineutrino flux and spectrum measured from nuclear reactors. Historical measurements of many of these isotopes are subject to a systematic bias referred to as the Pandemonium Effect, because the low-efficiency, high-precision detectors used to perform the measurements results in misinterpreting weak gamma cascades from high- energy levels as …

Pairing And Rotation-Induced Nuclear Exotica In Covariant Density Functional Theory, Saja Teeti

Theses and Dissertations

Covariant density functional theory (CDFT) is one of the modern theoretical tools for describing the nuclear structure physics of finite nuclei. Its performance is defined by underlying covariant energy density functionals (CEDFs). In this dissertation and within the framework of the CDFT, different physical properties of the ground and the excited states of rotating and non-rotating nuclei have been investigated.

A systematic global investigation of pairing properties based on all available experimental data on pairing indicators has been performed for the first time in the framework of covariant density functional theory. It is based on separable pairing interaction of Ref.\ …

Electron And Other Quarks As Particles Made Of Elementary Particles Of Charge E/3 And Mass Me/6, Polievkt Perov

College of Arts & Sciences Faculty Works

We suggest that the first-generation quarks are not elementary particles, but structures made of a basic elementary particle of charge e/3 and its antiparticle, interacting via an electrostatic force. The structures are suggested for d-quark as consisting of one positive and two negative basic elementary charges, for u-quark as a structure with one negative and three positive basic charges, for an electron as a quark with one positive and four negative basic charges, and for one more quark made of one positive and one negative basic charge. All the suggested structures are in a spinning motion and are stable. The …

Design And Construction Of A Longitudinally Polarized Solid Nuclear Target For Clas12, Victoria Lagerquist

Physics Theses & Dissertations

A new polarized nuclear target has been developed, constructed, and deployed at Jefferson Laboratory in Newport News, VA for use with the upgraded 12 GeV CEBAF (Continuous Electron Beam Accelerator Facility) accelerator and the Hall B CLAS12 (12 GeV CEBAF Large Acceptance Spectrometer) detector array. This ‘APOLLO’ (Ammonia POLarized LOngitudinally) target is a longitudinally polarized, solid ammonia, nuclear target which employs DNP (Dynamic Nuclear Polarization) to induce a net polarization in samples of protons (NH3) and deuterons (ND3) cooled to 1K via helium evaporation, held in a 5T polarizing field supplied by the CLAS12 spectrometer, and irradiated with 140 GHz …

Applying Instrumental Neutron Activation Analysis To Assess Air Pollution With Spanish Moss As A Bioindicator In The Low Country Of The Savannah River Basin, Christina Jiang

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Savanah River Basin is an area of 9,850 square miles that stretches from the border between South Carolina and Georgia, which empties into the Atlantic Ocean near Savannah, Ga. This area is home to surrounding cities, industrial sites, and the Savanah River Site. It is well documented that traffic, industrial operations, and agriculture contribute to worsening air pollution that needs to be monitored. While Tillandsia usneoides (Spanish moss) has been used in previous studies that prove it to be an effective biomonitor for air pollution and an accumulator of heavy metals, there have been no biomonitoring studies in the …

Experimental Study Of Neutron Shell Structure In Chromium-53 Via Neutron Transfer To Chromium-52, Dylan Todd Brown-Simms

Physics and Astronomy Honors Papers

A measurement of the ⁵²Cr(d,p) ⁵³Cr reaction at 16 MeV was performed using the Florida State University Super-Enge Split-Pole Spectrograph to determine single-neutron energies for the 2p3/2, 2p1/2, and 1f5/2 orbits. We were able to observe 24 unique states in ⁵³Cr. Using the energies and angular distributions we were able to calculate energy centroids. We discuss these preliminary results in the context of other N = 29 isotones and prospects for future work.

Fundamental Symmetries, Neutrons, And Neutrinos (Fsnn): Whitepaper For The 2023 Nsac Long Range Plan, William D. Williams, Et Al

Physics: Faculty Publications

Through the exploration of fundamental symmetries, and by using nuclei, neutrons, and neutrinos, nuclear physics addresses some of the most profound questions in science. Why does the universe contain so much more matter than antimatter? Are neutrinos their own antiparticles and where do their masses come from? What objects make up the dark matter that is responsible for most of the universe’s mass? Does nature contain more forces than the four we know about? Our Standard Model of nature’s particles and forces is incomplete because it does not answer these questions; new physics, from beyond the Standard Model (BSM) is …

Measuring Radiation Protection: Partners From Across The Nuclear Enterprise Evaluate The Radiation Protection Of Us Army Vehicles, Andrew W. Decker, Robert Prins

Faculty Publications

Recent mounting nuclear threats and postures from adversary nation-states, such as Russia, China, North Korea, and Iran, represent a clear danger to the interests and security of the United States of America and its Allies. To meet these threats, the 2022 Nuclear Posture Review requires the Department of Defense (DoD) to design, develop, and manage a combat-credible U.S. military which, among other prioritizations, is survivable. A survivable force can generate combat power despite adversary attacks. As such, the US Army must prepare today to set the conditions for successful conventional warfare on the nuclear battlefields of tomorrow. Our Army cannot …

Cross Sections Of The 83rb (P,Γ)84sr And 84kr(P,Γ)85rb Reactions At Energies Characteristic Of The Astrophysical Γ Process, M. Williams, B. Davids, G. Lotay, N. Nishimura, T. Rauscher, S. A. Gillespie, M. Alcorta, Alan M. Amthor, G. C. Ball, S. S. Bhattacharjee, V. Bildstein, W. N. Catford, D. T. Doherty, N. E. Esker, A. B. Garnsworthy, G. Hackman, K. Hudson, A. Lennarz, C. Natzke, B. Olaizola, A. Psaltis, C. E. Svensson, J. Williams, D. Walter, D. Yates

Faculty Journal Articles

We have measured the cross section of the 83 Rb ( p , γ ) 84 Sr radiative capture reaction in inverse kinematics using a radioactive beam of 83 Rb at incident energies of 2.4 and 2.7 A MeV. Prior to the radioactive beam measurement, the 84 Kr ( p , γ ) 85 Rb radiative capture reaction was measured in inverse kinematics using a stable beam of 84 Kr at an incident energy of 2.7 A MeV. The effective relative kinetic energies of these measurements lie within the relevant energy window for the γ process in supernovae. The central …

Modeling Radiation Exposure On Flight Missions To Analyze Aircrew Risk, Camila V. Quintero Hilsaca

Theses and Dissertations

GCR and SPE comprise the majority of the ionizing radiation experienced in the upper atmosphere within flight-altitude environments. Although previous studies have analyzed radiation doses from single sources on civilian flight operations, there is a lack of research focused on dose received by military personnel during flight from both sources simultaneously. In-flight radiation environments are modeled through the MCNP6 for two separate aircraft, an Air Force A-10 and a Boeing 737. Particle fluence values for galactic cosmic rays and solar particle events for four separate flight paths are determined using the CARI-7A software and the SIRE2 toolkit, respectively. MCNP6 code …

Automated Additive Layering Of Vat Polymerized Plastic Organic Scintillators, Chandler J. Moore

Theses and Dissertations

The current technology for fast neutron detection imaging is limited in achieving the required high spatial resolution, strong neutron discrimination, and practical time of manufacturing. Traditional fabrication methods require days of thermal polymerization and hundreds of man-hours to produce average resolution pixelated scintillator arrays. The present work helps to eliminate this limitation by developing an additive manufacturing technique to construct such detectors for use in in dual particle imaging applications. In this work, fast-, light-curing resins are used in a prototype automated assembly machine, capable of layering of individual light-cured resin layers and optical segmentation with a self-bonded specular reflector, …

One-Loop Corrections To Dihadron Production In Dis At Small X, Filip Bergabo

Dissertations, Theses, and Capstone Projects

We calculate the one-loop corrections to dihadron production in Deep Inelastic Scattering (DIS) at small x using the Color Glass Condensate formalism. We show that all UV and soft singularities cancel while the collinear divergences are absorbed into quark and anti quark-hadron fragmentation functions. Rapidity divergences lead to JIMWLK evolution of dipoles and quadrupoles describing multiple-scatterings of the quark anti-quark dipole on the target proton/nucleus. The resulting cross section is finite and can be used for phenomenological studies of dihadron angular correlations at small x in a future Electron-Ion Collider (EIC).

Azimuthal Anisotropy Of Different Quark-Flavored Particles In High Energy "Simulated" Proton-Proton Collisions, Mahmoud Rateb

Theses and Dissertations

Anisotropic flow in high energy heavy-ion collisions is taken as a key evidence for the formation of QGP for brief seconds right after the collisions. Hydrodynamic models including QGP formation are accurate at predicting the azimuthal anisotropy of the produced particles at low transverse momenta. At high momenta however, hydrodynamic models predict no azimuthal anisotropy for particles of different masses and quark-flavors; the logic being that because of their high momenta, the particles pass through the media without having any time to have any reactivity. This is contrary to results from experiments where measurements of particles of different quark flavors …

Study Of Fusion Reactions Of Some Light Projectiles On Medium Targets, Ruaa S. Abdullhussein, Ghuzlan Sarhan Ahmed, Sarah M. Obaid

Al-Bahir

Background and objectives: The investigation of heavy-ion (HI) induced fusion processes in order to comprehend the many mechanisms involved in these reactions has long been a focus of nuclear physics. The complicated structure and behavior of projectile and target nuclei with various projectile energy allows us to define the reaction process and may aid in the investigation of the potential of creating superheavy elements (SHE) in the laboratory.

Methods: The semiclassical and full quantum mechanical complete fusion cross section calculations and the distribution of the fusion barrier for the systems ¹²C+⁵⁰Ti,¹⁵N+⁵⁶Fe, …

Measurement Of Near-Threshold Proton Branching Ratios In 31s Important For Novae, Sudarsan Balakrishnan

LSU Doctoral Dissertations

Classical novae are stellar explosions that contribute to the nucleosynthesis of isotopes on the proton-rich side of the valley of stability up to ⁴⁰Ca. In ONe novae, the incompletely understood reaction rate of ³⁰P(p,γ)³¹S is known to strongly influence the production rate of several stable isotopes such as ³⁰Si, ³¹P, and ^32,33,34S. A precise measurement of this reaction rate has several potential implications towards matching astrophysical observables to the physical composition of the nova site -- the observed elemental abundance ratios of O/S and S/Al have been suggested as useful `thermometers' to gauge …