Nuclear Theory·nucl-th

Monday·March 22, 2021

13 papers—9 primary·4 cross-listed

10
[Submitted on 19 Mar 2021] (cross-list from nucl-ex)
Production cross sections and angular distributions of neutron-rich rare isotopes from 15 MeV/nucleon Kr-induced collisions: toward the r-process path
O. Fasoula🇬🇷 · G.A. Souliotis🇬🇷 · Y.K. Kwon🇰🇷 · K. Tshoo🇰🇷 · M. Veselsky🇨🇿 · S.J. Yennello🇺🇸 · A. Bonasera🇺🇸
We present our recent study of cross sections and angular distributions of projectile fragments from heavy-ion reactions at beam energy of 15 MeV/nucleon. We studied the production cross sections and the angular distributions of neutron-rich nuclides from collisions of a 86 Kr (15 MeV/nucleon) beam with heavy targets ( 64 Ni, 124 Sn and 238 U). Experimental data from our previous work at Texas A & M were compared with model calculations. Our calculations were based on a two-step approach: the dynamical stage of the collision was described with, first, the phenomenological Deep-Inelastic Transfer model (DIT) and, alternatively, with the microscopic Constrained Molecular Dynamics model (CoMD). The de-excitation of the hot heavy projectile fragments was performed with the Statistical Multifragmentation Model (SMM). An overall good discription of the available data was obtained with the models employed. Furthermore, we performed calculations with a radioactive beam of 92 Kr (15 MeV/nucleon) interacting with a target of 238 U. We observed that the multinucleon transfer mechanism leads to extremely neutron-rich nuclides toward and beyond the astrophysical r-process path.
Comments:
15 pages, 8 figures
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2103.10688 [pdf]
4 citations
11
[Submitted on 19 Mar 2021] (cross-list from nucl-ex)
Momentum Distributions of Projectile Fragments from Heavy-ion Peripheral Collisions at 15 MeV/nucleon with Emphasis on Trans-Projectile Isotopes
S. Koulouris🇬🇷 · G.A. Souliotis🇬🇷 · I. Dimitropoulos🇬🇷 · O.Fasoula🇬🇷 · K. Palli🇬🇷 · M. Veselsky🇨🇿 · A. Bonasera🇺🇸
This paper presents our recent efforts to study the momentum distributions as well as the production of neutron-rich rare isotopes with heavy-ion beams in the energy region of 15 MeV/nucleon. Experimental cross sections of neutron-rich nuclides from collisions of a 86 Kr (15 MeV/nucleon) beam with 64 Ni and 58 Ni targets are presented. Experimental data were obtained from the previous work of our group with the MARS mass spectrometer at the Cyclotron Institute of Texas A&M University. On that note, detailed calculations of yields and momentum distributions of neutron-rich projectile-like fragments are presented for the interaction of 86 Kr with 64 Ni and compared with the aforementioned experimental data. The calculations were based on a two-step general approach: the dynamical stage of the primary interaction was described with the phenomenological deep-inelastic transfer model (DIT) and the microscopic constrained molecular dynamics model (CoMD); the deexcitation stage of the excited projectile fragments was described with the statistical binary-decay model GEMINI. The experimental data show an enhancement in the production of neutron-rich isotopes close to the projectile, and interestingly of heavier than the projectile neutron-rich nuclei. The behaviour of the data is relative to the predictions of the CoMD/GEMINI calculation. The study of the momentum distributions offers a novel route to study the reaction mechanism that dominates the production of the fragments of interest in peripheral heavy-ion collisions at intermediate energies. In the future, we plan to analyze experimental data that were obtained from the MAGNEX spectometer at the INFN-LNS in Catania, Italy.
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2103.10691 [pdf]
0 citations
12
[Submitted on 19 Mar 2021] (cross-list from nucl-ex)
Measurement of the neutron charge radius and the role of its constituents
H. Atac🇺🇸 · M. Constantinou🇺🇸 · Z.-E. Meziani🇺🇸 · M. Paolone🇺🇸 · N. Sparveris🇺🇸
The neutron is a cornerstone in our depiction of the visible universe. Despite the neutron zero-net electric charge, the asymmetric distribution of the positively- (up) and negatively-charged (down) quarks, a result of the complex quark-gluon dynamics, lead to a negative value for its squared charge radius, $⟨ r_{n}^{2} ⟩$ . The precise measurement of the neutron's charge radius thus emerges as an essential part of unraveling its structure. Here we report on a $⟨ r_{n}^{2} ⟩$ measurement, based on the extraction of the neutron electric form factor, $G_{E}^{n}$ , at low four-momentum transfer squared $(Q^{2})$ by exploiting the long known connection between the $N \to Δ$ quadrupole transitions and the neutron electric form factor. Our result, $⟨ r_{n}^{2} ⟩ = - 0.110 \pm 0.008 (fm^{2})$ , addresses long standing unresolved discrepancies in the $⟨ r_{n}^{2} ⟩$ determination. The dynamics of the strong nuclear force can be viewed through the precise picture of the neutron's constituent distributions that result into the non-zero $⟨ r_{n}^{2} ⟩$ value.
Comments:
https://doi.org/10.1038/s41467-021-22028-z
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2103.10840 [pdf]
Nature Commun.(2021)·51 citations
13
[Submitted on 19 Mar 2021] (cross-list from hep-ph)
Coherent elastic neutrino-nucleus scattering with the $ν$ BDX-DRIFT directional detector at next generation neutrino facilities
D. Aristizabal Sierra🇨🇱 · Bhaskar Dutta🇺🇸 · Doojin Kim🇺🇸 · Daniel Snowden-Ifft🇺🇸 · Louis E. Strigari🇺🇸
We discuss various aspects of a neutrino physics program that can be carried out with the neutrino Beam-Dump eXperiment DRIFT ( $ν$ BDX-DRIFT) detector using neutrino beams produced in next generation neutrino facilities. $ν$ BDX-DRIFT is a directional low-pressure TPC detector suitable for measurements of coherent elastic neutrino-nucleus scattering (CE $ν$ NS) using a variety of gaseous target materials which include carbon disulfide, carbon tetrafluoride and tetraethyllead, among others. The neutrino physics program includes standard model (SM) measurements and beyond the standard model (BSM) physics searches. Focusing on the Long Baseline Neutrino Facility (LBNF) beamline at Fermilab, we first discuss basic features of the detector and estimate backgrounds, including beam-induced neutron backgrounds. We then quantify the CE $ν$ NS signal in the different target materials and study the sensitivity of $ν$ BDX-DRIFT to measurements of the weak mixing angle and neutron density distributions. We consider as well prospects for new physics searches, in particular sensitivities to effective neutrino non-standard interactions.
Comments:
14 pages, 10 figures, 1 table
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2103.10857 [pdf]
PRD(2021)·23 citations

Affiliations

first authorsco-authorsvia INSPIRE

Production cross sections and angular distributions of neutron-rich rare isotopes from 15 MeV/nucleon Kr-induced collisions: toward the r-process path

Momentum Distributions of Projectile Fragments from Heavy-ion Peripheral Collisions at 15 MeV/nucleon with Emphasis on Trans-Projectile Isotopes

Measurement of the neutron charge radius and the role of its constituents

Coherent elastic neutrino-nucleus scattering with the νBDX-DRIFT directional detector at next generation neutrino facilities

Affiliations

Coherent elastic neutrino-nucleus scattering with the $ν$ BDX-DRIFT directional detector at next generation neutrino facilities