Bulletin of the American Physical Society
6th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japan
Sunday–Friday, November 26–December 1 2023; Hawaii, the Big Island
Session F02: Nuclear Reaction II |
Hide Abstracts |
Chair: Alan Wuosmaa, University of Connecticut Room: Hilton Waikoloa Village Kona 1 |
Thursday, November 30, 2023 9:00AM - 9:15AM |
F02.00001: Isotopic production of 99Tc via proton- and deuteron-induced reactions and new analytical model for its longitudinal momentum distribution Riku Matsumura, Hideaki Otsu, He Wang, Hiroyoshi Sakurai, Daiki Nishimura, Hiroyuki Takahashi, Shoko Takeshige, Masaomi Tanaka, Yasuhiro Togano The disposal of spent fuels from nuclear power plants is a worldwide problem. The high-level radioactive wastes are the residual of spent fuels, which contain minor actinides and fission products. To evaluate the reaction cross sections of the long-lived fission products, we have systematically measured the p- and d-induced cross sections for 90Sr, 137Cs [1], 93Zr [2], 107Pd [3], etc. As a next step, we started a study on 99Tc (T1/2 = 2.1×105 y). Tc is the element with atomic number 43 and has no stable isotopes. |
Thursday, November 30, 2023 9:15AM - 9:30AM |
F02.00002: Gamma-ray and Neutron Production Cross Sections for Neutron Irradiation of 12C Anastasia Georgiadou, Bethany L Goldblum, Josh A Brown, Thibault A Laplace, Lee A Bernstein, Jon C Batchelder, Darren L Bleuel, Christopher Brand, Brayden Buckley, Joseph M Gordon, Charles J Henderson, Joong W Lee, Tyler S Johnson, Keenan Myers, Tyler S Nagel, Jacob Sebastian, Andrew S Voyles Improved neutron inelastic scattering cross sections were recently identified as a top priority nuclear data need, important for basic science, and a range of applications in nuclear energy, stockpile stewardship, and proliferation detection. For reactions on carbon, γ-ray, and neutron emission probabilities are needed for active neutron interrogation applications due to the prevalence of carbon in structural materials, controlled substances, and detector components. Using the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory, a broad-spectrum neutron beam was made incident on a 99.8% pure natC target. The Gamma Energy Neutron Energy Spectrometer for Inelastic Scattering (GENESIS), which includes HPGe detectors and an array of EJ-309 organic liquid scintillators, was used to measure energy- and angular-differential γ-ray and neutron emission spectra as a function of incident neutron energy. Initial results of 12C(n,n’γ) will be presented, including discussions of a forward modeling approach that leverages reaction model calculations and GENESIS observables to determine the nuclear physics quantities of interest. This work increases the utility of active neutron interrogation systems and provides benchmarks to facilitate reaction modeling improvements. |
Thursday, November 30, 2023 9:30AM - 9:45AM |
F02.00003: Surrogate reaction theory for obtaining (n,n') and (n,2n) cross sections from charged-particle scattering data Jutta E Escher To obtain cross sections for neutron-induced reactions we often have to resort to indirect methods, in particular if the target nucleus is unstable. In the past few years, the surrogate reactions method [1] has been successfully applied to obtain neutron capture cross sections from alternative reactions [2-4]. In this presentation, I will discuss extensions of the surrogate approach that enable us to determining (n,n’) and (n,2n) cross sections indirectly. Challenges, in particular for nuclear theory, will be addressed and results for 90Zr(n,n’) and 90Zr(n,2n) benchmark cases shown. |
Thursday, November 30, 2023 9:45AM - 10:00AM |
F02.00004: 149Tb cross sections for basic and applied science Alan B McIntosh, Laura A McCann, Lauren A McIntosh, Kris Hagel, Philip Adsley, John Santucci, Sherry J Yennello, Jonathan T Morrell, Etienne Vermulen, Matt Gott, Connor Mohs, Claus Mueller-Gatermann, Jeremias Garcia Duarte, Jason T Harke, Richard O Hughes, Yonatan Mishnayot, Aaron S Tamashiro Accurate knowledge of reaction cross sections is needed for astrophysical nucleosynthesis, isotope production, reactor design, and stockpile science. Measurement of key reactions, and systematic measurements along isotopic chains, can be used to improve the accuracy of model predictions. I will describe our measurements of 149(g)Tb and 149(m)Tb production cross sections, as well as cross sections for nearly a dozen other isotopes in the region. The unique decay properties of 149(g)Tb make it particularly compelling for therapy and diagnostics for targeted alpha therapy for cancer treatment. We use beams of 1H, 6Li, 7Li on targets of enriched Sm, Eu, Gd, and will measure with beams of alpha particles in the future. The lanthanide targets were fabricated by physical vapor deposition (metallic) and molecular deposition (oxides). Short lived decays from metastable states are measured immediately after irradiation with the HPGe clover array Hyperion; long lived decays are measured with Hyperion and additional HPGe detectors. Our future experiments focusing on 149(g)Tb will measure an excitation function with a single beam by using a stack of thin targets and degraders. |
Thursday, November 30, 2023 10:00AM - 10:15AM |
F02.00005: Cross-calibrations of the D-T γ-to-neutron and D-3He γ-to-proton branching ratios against the 12C(n,n’γ)12C reaction Justin Jeet, Alex Zylstra, Mike S Rubery, Yongho Kim, Kevin D Meaney, Zaarah Mohamed, Chad J Forrest, Vladimir Glebov The deuterium-tritium (D-T) γ-to-neutron branching ratio (3H(d,γ)5He/3H(d,n)4He) has been determined previously in beam-target based experiments as well as in inertial confinement fusion (ICF) experiments. There is however large discrepancies in the obtained results. A benefit of ICF based measurements is the ability to achieve lower center of mass energies as compared to accelerators, and temporally separate the signal from neutron induced backgrounds. A more precise value for the branching ratio based on data taken at the OMEGA facility has been determined which relies on a cross-calibration against the better known 12C neutron inelastic scattering cross section (12C(n,n’γ)12C) in a puck-based experiment involving the Gas Cherenkov Detector (GCD-3). A D-T branching ratio value of (4.6 ± 0.6) × 10−5 is determined by this method. [1] The results of a more recent and optimized experiment to measure the D-T branching ratio are discussed as well as a measurement of the D-3He -to-proton branching ratio, using similar techniques, to provide better precision than reported by previous experiments which are limited to 33%. |
Thursday, November 30, 2023 10:15AM - 10:30AM |
F02.00006: Deuterium induced reactions on 6Li Som N Paneru, Thomas L Bailey, Esther L Cidoncha, Adam M Clark, Richard J deBoer, Michael T Febbraro, Christopher A Fichtl, Panagiotis Gastis, Joachim Goerres, Beka Kelmar, Toby King, Sean A Kuvin, Hye Y Lee, Khachatur Manukyan, Tony Miller, Michelle Mosby, Jason Nattress, Austin D Nelson, Christopher Prokop, Daniel Robertson, Thomas Ruland, S Shahina, Edward Stech, Wanpeng Tan Deuteron-induced reactions on 6Li are important for nuclear structure studies and for nuclear applications. The partial cross section and the angular distribution information for 6Li(d, n)7Be reaction are lacking in literature even after several measurements, which is a source of inconsistencies between various R-matrix evaluations of 8Be system. A new measurement of deuterium induced reactions on 6Li target was performed at University of Notre Dame in collaboration with Oak Ridge National Laboratory and University of Notre Dame to fill in important gaps in the existing data. The experiment was carried out for the deuterium energy range from 1.8 to 15 MeV with angular coverage of 10o-170o in laboratory frame of reference. The experiment simultaneously measured the neutrons, charged particles, and gammas from the reaction. The experimental details and preliminary results for various reactions channels from the ongoing analysis will be discussed. Also, the results for 6Li(d, n)7Be angle integrated cross section from the activation measurement will be presented. In addition, a multi-channel R-matrix analysis is performed to fit the available data for 8Be system simultaneously using phenomenological R-matrix code AZURE2. The details of the R-matrix analysis and preliminary results will be presented and compared with the Energy Dependent Analysis (EDA) fit providing valuable insight into improving the future evaluation. |
Thursday, November 30, 2023 10:30AM - 10:45AM |
F02.00007: Observation of d(t,n)α neutrons following d(d,p)t reactions in a deuterium gas cell John P Lestone, Mark B Chadwick, Werner Tornow, Jerry Wilhelmy, Forrest Q Friesen, Sean Finch, Ethan Mancil In order to benchmark methods used to calculate reaction-in-flight fusion reactions in ICF, and address issues related to the first claimed observation of d(t,n)α reactions in 1938, secondary d(t,n)α reactions have been observed following d(d,p)t reaction in deuterium gas. A pulsed ~100 nA 2.2-MeV deuterium beam from the TUNL FN Tandem was injected into a cylindrical multi-atmosphere deuterium gas target. The incident beam ran along the target cylinder’s 3-cm symmetry axis after its passage through a Havar entrance foil. Two different Havar foil thicknesses were used to obtain 1.5-MeV and 0.5-MeV deuteron beams entering the deuterium cell. The cylinder’s radius was 2 cm to allow for d(d,p)t tritons emitted perpendicular to the beam to range out in the deuterium gas. The neutron emission from the cell was observed via its time-of-flight to a liquid-scintillator placed at various angles to the beam direction, at a distance of ~ 2 m. Pulse-shape discrimination techniques were used to separate neutron and gamma-ray signals seen in the liquid scintillator. The observed probability for inducing d(t,n)α fusions in the cell per d(d,p)t reaction will be compared to theory. |
Thursday, November 30, 2023 10:45AM - 11:00AM |
F02.00008: Abstract Withdrawn
|
Thursday, November 30, 2023 11:00AM - 11:15AM |
F02.00009: Measurement of the decay of fission products for nuclear forensics Andrea Mattera, Elizabeth McCutchan, Jin Wu, Vandana Tripathi, Catur Wibisono, Soumik Bhattacharya, Shuya Ota, Marian Jandel, Samuel L Tabor, Peter C Bender, Timothy Gray, James M Allmond Detection of fission products (FPs) is at the basis of several applications, from reactor science, to non-proliferation and nuclear forensics. In most cases, an accurate quantification of FPs is only possible when the decay data of these isotopes - such as half-life, characteristic gamma-ray energies and intensities - are well known. This is not always the case, and - for many FPs - the current knowledge of decay data comes from measurements that were performed when gamma-ray spectroscopy was in its infancy. |
Thursday, November 30, 2023 11:15AM - 11:30AM |
F02.00010: The n+88Zr transmission experiment at DICER at LANSCE Thanos Stamatopoulos, Paul Koehler, Aaron J Couture, Brad J DiGiovine, Artem Matyskin, Veronika Mocko, Jonathan T Morrell, Ellen M O'Brien, Gencho Y Rusev, John L Ullmann, Christiaan E Vermeulen The new Device for Indirect Capture Experiments on Radionuclides (DICER) installed at the Los Alamos Neutron Science Center (LANSCE), explores the possibility of determining neutron capture rates through the analysis of transmission data at the resolved resonance region. The synergy between DICER and the Isotope Production Facility (IPF), both at LANSCE, resulted in the measurement of a 88Zr sample (t1/2=83.4 days). A description of the device, the experimental preparation and the exciting results that explain the enormous neutron capture cross section of 88Zr, will be presented. |
Thursday, November 30, 2023 11:30AM - 11:45AM Withdrawn |
F02.00011: Role of isospin composition in low energy nuclear fusion Christian Ross, Richard Gumbel, Sait A Umar We employ a microscopic approach that examines the impact of isospin dynamics on the process of low energy nuclear fusion along an isotope chain and dependence on deformation. Our method utilizes the density constrained time-dependent Hartree-Fock theory (DC-TDHF), where isoscalar and isovector characteristics of the energy density functional (EDF) are examined in turn. This approach is applied to a series of fusion interactions of 176Yb with increasingly neutron rich isotopes of Calcium. By evaluating the contributions from the isoscalar and isovector components of the EDF, we look to quantify the influence of isospin composition on the conditions under which fusion is most likely to take place. Our findings reveal that, in non-symmetric systems, the isovector dynamics play a significant role. It's typical effect is a reduction in the potential barrier, which turns into enhancement for neutron-rich systems. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700