Nuclear Commons^™

Measurement Of The Differential And Total Cross Sections Of The ᵧd→Kºʌ(P) Reaction Within The Resonance Region, N. Compton, C. E. Taylor, K. Hicks, P. Cole, N. Zachariou, Y. Ilieva, P. Nadel-Turonski, E. Klempt, V. A. Nikonov, A. V. Sarantsev, C. E. Hyde, M. Khachatryan, A. Klein, Y. Prok, B. Torayev, J. Zhang

Physics Faculty Publications

We report the first measurement of differential and total cross sections for the γd →K⁰ Λ(p)reaction, using data from the CLAS detector at the Thomas Jefferson National Accelerator Facility. Data collected during two separate experimental runs were studied with photon-energy coverage 0.8-3.6 GeV and 0.5-2.6 GeV, respectively. The two measurements are consistent giving confidence in the method and determination of systematic uncertainties. The cross sections are compared with predictions from the KAON-MAID theoretical model (without kaon exchange), which deviate from the data at higher W and at forward kaon angles. These data, along with previously published cross sections for …

Nucleon-Nucleon Correlations, Short-Lived Excitations, And The Quarks Within, Or Hen, Gerald A. Miller, Eli Piasetzky, Lawrence B. Weinstein

Physics Faculty Publications

This article reviews our current understanding of how the internal quark structure of a nucleon bound in nuclei differs from that of a free nucleon. The interpretation of measurements of the European Muon Collaboration (EMC) effect for valence quarks, a reduction in the deep inelastic scattering cross-section ratios for nuclei relative to deuterium, and its possible connection to nucleon-nucleon short-range correlations (SRCs) in nuclei are focused on. This review and new analysis (involving the amplitudes of non-nucleonic configurations in the nucleus) of the available experimental and theoretical evidence shows that there is a phenomenological relation between the EMC effect and …

Target And Beam-Target Spin Asymmetries In Exclusive Pion Electroproduction For Q² > 1 Gev² . Ii. Ep→ Eπºp, Clas Collaboration, K. P. Adhikari, D. Adikaram, M. J. Amaryan, S. Bültmann, N. Guler, S E. Kuhn, A. Klein, S. Koirala, B. Torayev, J. Zhang, Z. W. Zhao

Physics Faculty Publications

Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π⁰ electroproduction reaction γ^∗p→pπ⁰, expanding an analysis of the γ^∗p→nπ⁺ reaction from the same experiment. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic ranges covered are 1.1 < W < 3 GeV and 1 < Q²< 6 GeV² . Results were obtained for about 5700 bins in W, Q², cos(θ^∗) , and ϕ^∗. The beam-target asymmetries were found to generally be greater than zero, with …

Optimization Of The Rf Cavity Heat Load And Trip Rates For Cebaf At 12 Gev, H. Zhang, Y. Roblin, A. Freyberger, G. Krafft, B. Terzić

Physics Faculty Publications

The Continuous Electron Beam Accelerator Facility at JLab has 200 RF cavities in the north linac and the south linac respectively after the 12 GeV upgrade. The purpose of this work is to simultaneously optimize the heat load and the trip rate for the cavities and to reconstruct the pareto-optimal front in a timely manner when some of the cavities are turned down. By choosing an efficient optimizer and strategically creating the initial gradients, the pareto-optimal front for no more than 15 cavities down can be re-established within 20 seconds.

Measurement Of Two-Photon Exchange Effect By Comparing Elastic E ± P Cross Sections, D. Rimal, D. Adikaram, B. A. Raue, L. B. Weinstein, J. Arrington, W. K. Brooks, M. Ungaro, K. P. Adhikari, A. V. Afanasev, Z. Akbar

Physics Faculty Publications

Background: The electromagnetic form factors of the proton measured by unpolarized and polarized electron scattering experiments show a significant disagreement that grows with the squared four-momentum transfer (Q²) . Calculations have shown that the two measurements can be largely reconciled by accounting for the contributions of two-photon exchange (TPE). TPE effects are not typically included in the standard set of radiative corrections since theoretical calculations of the TPE effects are highly model dependent, and, until recently, no direct evidence of significant TPE effects has been observed.

Purpose: We measured the ratio of positron-proton to electron-proton elastic-scattering cross …

Inclusive Neutrino Scattering Off The Deuteron At Low Energies In Chiral Effective Field Theory, A. Baroni, R. Schiavilla

Physics Faculty Publications

Cross sections for inclusive neutrino scattering off the deuteron induced by neutral and charge-changing weak currents are calculated from threshold up to 150 MeV energies in a chiral effective field theory including high orders in the power counting. Contributions beyond leading order (LO) in the weak current are found to be small, and increase the cross sections obtained with the LO transition operators by a couple of percent over the whole energy range 0–150 MeV. The cutoff dependence is negligible, and the predicted cross sections are within ∼2% of, albeit consistently larger than, corresponding predictions obtained in conventional meson-exchange frameworks.

A First Experimental Limit On The Relative Rates Of Muon Capture On Deuterium From The Quartet And Doublet Hyperfine Spin States Of The Μd Atom, Ray Kreswell Neely

Theses and Dissertations--Physics and Astronomy

The MuSun experiment will determine the muon capture rate on deuterium (µ− + d → n + n + ν_µ) from the doublet hyperfine spin state, Λ_d, of muonic deuterium to a precision of 1.5%. Muon capture can occur from either the quartet or doublet state of the 1S orbital of the µd atom; however, the V-A nature of the process strongly suppresses the rate of capture from the quartet state, Λ_q. Muons in ultrapure deuterium gas may also catalyze d+d → ³He+n fusion through the formation …

Neutron-Antineutron Transitions: Exploring B – L Violation With Quarks, Xinshuai Yan

Theses and Dissertations--Physics and Astronomy

In the Standard Model (SM), the quantity baryon number (B) − lepton number (L), B − L, is perfectly conserved. Therefore, the observation of B − L violation would reveal the existence of physics beyond the SM. Traditionally, given the severe experimental constraints on |∆B| = 1 processes, B − L violation with baryons is probed via neutron-antineutron (n − n̄) oscillations, although this process suffers from quenching in the presence of external fields or matter.

In this dissertation, we discuss another possibility, n − n̄ conversion, in which the |∆ …

Studying Transverse Momentum Dependent Distributions In Polarized Proton Collisions Via Azimuthal Single Spin Asymmetries Of Charged Pions In Jets, James Kevin Adkins

Theses and Dissertations--Physics and Astronomy

A complete, fundamental understanding of the proton must include knowledge of the underlying spin structure. The transversity distribution, h₁(x), which describes the transverse spin structure of quarks inside of a transversely polarized proton, is only accessible through channels that couple h₁(x) to another chiral odd distribution, such as the Collins fragmentation function (Δ^N D_π/q^↑(z,j_T)). Significant Collins asymmetries of charged pions have been observed in semi-inclusive deep inelastic scattering (SIDIS) data. These SIDIS asymmetries combined with e⁺e^- process asymmetries have allowed for …

Disconnected-Sea Quarks Contribution To Nucleon Electromagnetic Form Factors, Raza Sabbir Sufian

Theses and Dissertations--Physics and Astronomy

We present comprehensive analysis of the light and strange disconnected-sea quarks contribution to the nucleon electric and magnetic form factors. The lattice QCD estimates of strange quark magnetic moment G^s_M (0) = −0.064(14)(09) μ_N and the mean squared charge radius ⟨r²_s⟩_E = −0.0043(16)(14) fm² are more precise than any existing experimental measurements and other lattice calculations. The lattice QCD calculation includes ensembles across several lattice volumes and lattice spacings with one of the ensembles at the physical pion mass. We have performed a simultaneous chiral, infinite volume, and continuum extrapolation in …

A Measurement Of The Parity Violating Asymmetry In The Neutron Capture On 3He At Sns, Md Latiful Kabir

Theses and Dissertations--Physics and Astronomy

Weak nucleon nucleon couplings are largely unknown because of the involved theoretical and experimental challenges. Theoretically the topic is difficult due to the non-perturbative nature of the strong interaction, which makes calculations of the couplings challenging. Experimentally, the topic is difficult given that 1) the observables are determined by ratios between strong couplings and weak couplings which differ in size by seven orders of magnitude, and 2) theoretically clean and predictable measurements are almost always restricted to simple systems that do not allow for effects that enhance the size of the asymmetry. However parity violation (PV) can be used to …

Improving Nuclear Safety, Security, And Nonproliferation In Northeast Asia Through Multinational Approach, Viet Phuong Nguyen

International Journal of Nuclear Security

No abstract provided.

Nuclear Power: Black Sky Liability Or Black Sky Asset?, Sherrell R. Greene

International Journal of Nuclear Security

Ready access to abundant electricity is a key enabler of modern life. During the past decade the vulnerability of Critical Infrastructure sectors in the U.S. to a variety of natural hazards and man-made threats has become increasingly apparent. The electrical infrastructure (the “Grid”) is the foundation for all other critical civil infrastructures upon which our society depends. Therefore, protection of the Grid is an energy security, homeland security, and national security issue of highest importance. Geomagnetic disturbances (GMD) induced by solar coronal mass ejections (CMEs), electromagnetic pulse (EMP) attacks, and cyber attacks are three events having the potential to plunge …

Addressing The Tunnel Threat At Nuclear Facilities: A Case Study, Md. Mobasher Ahmed

International Journal of Nuclear Security

No abstract provided.

Janus Realized: The Use Of Social Media As A Means Of Transparency Nuclear Communication To The Public, Frances Bachstein

International Journal of Nuclear Security

No abstract provided.

Letter From The Editor

International Journal of Nuclear Security

No abstract provided.

Implementation Of The 1995 Middle East Resolution: A Vital Lifeline To The Extension And Success Of The Non-Proliferation Treaty, Haidy Y. Ghoname, Howard Lewis Hall

International Journal of Nuclear Security

This study highlights the core non-proliferation dilemmas we face and suggests an effective mechanism for reviving the spirit and the hope of the Non-Proliferation Treaty. An indispensable key to the treaty calls for a rethinking of what we believe should be referred to as its four pillars: disarmament, non-proliferation, peaceful uses of nuclear energy, and implementation of the 1995 Middle East Resolution. We seek to contribute to the renaissance of the non-proliferation regime by addressing seven dilemmas that arise from the way various Non-Proliferation Treaty participants pursue the goals of the four pillars undergirding the treaty. This study highlights …

Table Of Contents

International Journal of Nuclear Security

No abstract provided.

A New Pathway To Enhance The Nuclear Security Regime, Francesca Giovannini

International Journal of Nuclear Security

The paper investigates the approach used by a new set of regional institutions, the Disaster Preparedness and Risk Management Organizations (DPRMOs), in strengthening regional governance and cooperation. It also inquires in what ways these new institutions might indirectly contribute to the establishment of a more cohesive global nuclear security framework. More specifically, through the examination of the case of Southeast Asia, the paper argues that these institutions, albeit without a specific and direct mandate to operate in the nuclear security domain, are fundamentally strengthening states’ capacity to assess risks and threats and to map vulnerabilities in timely fashion. They are …

Modern Advancements In Post-Detonation Nuclear Forensic Analysis, S. Adam Stratz, Jonathan A. Gill, John D. Auxier Ii, Howard L. Hall

International Journal of Nuclear Security

Deterring nuclear terrorism is a critical national asset to support the preclusion of non-state actors from initiating a nuclear attack on the United States. Successful attribution of a detonated nuclear weapon allows for timely responsive measures that prove essential in the period following a nuclear event. In conjunction with intelligence and law enforcement evidence, the technical nuclear forensics (TNF) post-detonation community supports this mission through the development and advancement of expertise to characterize weapon debris through a rapid, accurate, and detailed approach. Though the TNF field is young, numerous strides have been made in recent years toward a more robust …