Microscopic description of spin distributions in multinucleon tranfer reactions
Abstract
Background: The generation of spin distributions in fission fragments has attracted substantial interest in recent years and its mechanism is becoming clear alongside the refined description with microscopic theories. In contrast, the microscopic origin of spin distributions in reaction products remain largely unexplored. Methods: Three-dimensional TDHF calculations are performed for multinucleon transfer processes in the 40Ca + 124Sn reaction at Ec.m. ≃ 128.54 MeV using the Skyrme SLy5 energy density functional. To obtain spin distributions in each transfer channel, the particle-number projection (PNP) and the angular-momentum projection (AMP) are simultaneously achieved for a reaction product. Results: By performing PNP+AMP for TDHF wave functions after collisions, spin-dependent transfer cross sections are calculated for projectile-like fragments (PLFs). From the results, we find that abundant spin distributions can be obtained from the TDHF wave functions. For one-nucleon addition and removal channels, the calculated spin values agree well with those of single-particle states in the pf- and sd-shell, respectively. Moreover, for a-few-nucleon transfer channels, we show that the obtained spin distributions can be well explained by combinations of total angular momenta of those single-particle states. Furthermore, as the number of transferred nucleons increases, we find that the calculated spin distributions exhibit a smooth singly-peaked shape with a long tail as a function of J, which resembles that of empirical spin distributions for thermally equilibrated fragments. An exploratory calculation for induced fission of 240Pu is also carried out, obtaining similar results as in multinucleon transfer reactions. (shorted due to the arXiv's word limit)
Related
- Microscopic description of the fission process including intrinsic excitations. Part II: 240Pu excited and asymmetric fission paths within the Schrodinger Collective
- Microscopic description of the fission process including intrinsic excitations. Part I: 240Pu adiabatic and asymmetric fission path within the Schrodinger Collective Intrinsic Model
- Microscopic description of the fission process including intrinsic excitations. Part III: 240Pu fission dynamics along 1D asymmetric paths within the Schrodinger Collective Intrinsic Model
- Nonlocal Electrostatic Field Theory from Microscopic Description
- Microscopic Spin-Parity Distributions of Fission Fragments
BibTeX
@misc{koga2026microscopic,
title = {{Microscopic description of spin distributions in multinucleon tranfer reactions}},
author = {Kotaro Koga and Kazuyuki Sekizawa},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.12739},
eprint = {2609.12739},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.12739},
}
RIS
TY - UNPB
TI - Microscopic description of spin distributions in multinucleon tranfer reactions
AU - Kotaro Koga
AU - Kazuyuki Sekizawa
PY - 2026
DA - 2026/09/25
PB - arXiv
DO - 10.48550/arxiv.2609.12739
UR - https://arxiv.org/abs/2609.12739
AB - Background: The generation of spin distributions in fission fragments has attracted substantial interest in recent years and its mechanism is becoming clear alongside the refined description with microscopic theories. In contrast, the microscopic origin of spin distributions in reaction products remain largely unexplored. Methods: Three-dimensional TDHF calculations are performed for multinucleon transfer processes in the ^40Ca + ^124Sn reaction at E_c.m. ≃ 128.54 MeV using the Skyrme SLy5 energy density functional. To obtain spin distributions in each transfer channel, the particle-number projection (PNP) and the angular-momentum projection (AMP) are simultaneously achieved for a reaction product. Results: By performing PNP+AMP for TDHF wave functions after collisions, spin-dependent transfer cross sections are calculated for projectile-like fragments (PLFs). From the results, we find that abundant spin distributions can be obtained from the TDHF wave functions. For one-nucleon addition and removal channels, the calculated spin values agree well with those of single-particle states in the pf- and sd-shell, respectively. Moreover, for a-few-nucleon transfer channels, we show that the obtained spin distributions can be well explained by combinations of total angular momenta of those single-particle states. Furthermore, as the number of transferred nucleons increases, we find that the calculated spin distributions exhibit a smooth singly-peaked shape with a long tail as a function of J, which resembles that of empirical spin distributions for thermally equilibrated fragments. An exploratory calculation for induced fission of ^240Pu is also carried out, obtaining similar results as in multinucleon transfer reactions. (shorted due to the arXiv's word limit)
ER -