Microscopic dynamical description of proton-induced fission with the constrained molecular dynamics model

N. Vonta, G. A. Souliotis, M. Veselsky, and A. Bonasera
Phys. Rev. C 92, 024616 – Published 24 August 2015

Abstract

The microscopic description of nuclear fission still remains a topic of intense basic research. Understanding nuclear fission, apart from a theoretical point of view, is of practical importance for energy production and the transmutation of nuclear waste. In nuclear astrophysics, fission sets the upper limit to the nucleosynthesis of heavy elements via the r process. In this work we initiated a systematic study of intermediate-energy proton-induced fission using the constrained molecular dynamics (CoMD) code. The CoMD code implements an effective interaction with a nuclear matter compressibility of K=200 (soft equation of state) with several forms of the density dependence of the nucleon-nucleon symmetry potential. Moreover, a constraint is imposed in the phase-space occupation for each nucleon restoring the Pauli principle at each time step of the collision. A proper choice of the surface parameter of the effective interaction has been made to describe fission. In this work, we present results of fission calculations for proton-induced reactions on: (a) Th232 at 27 and 63 MeV; (b) U235 at 10, 30, 60, and 100 MeV; and (c) U238 at 100 and 660 MeV. The calculated observables include fission-fragment mass distributions, total fission energies, neutron multiplicities, and fission times. These observables are compared to available experimental data. We show that the microscopic CoMD code is able to describe the complicated many-body dynamics of the fission process at intermediate and high energy and give a reasonable estimate of the fission time scale. Sensitivity of the results to the density dependence of the nucleon symmetry potential (and, thus, the nuclear symmetry energy) is found. Further improvements of the code are necessary to achieve a satisfactory description of low-energy fission in which shell effects play a dominant role.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
9 More
  • Received 15 November 2014
  • Revised 10 July 2015

DOI:https://doi.org/10.1103/PhysRevC.92.024616

©2015 American Physical Society

Authors & Affiliations

N. Vonta1, G. A. Souliotis1,*, M. Veselsky2, and A. Bonasera3,4

  • 1Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens 15771, Greece
  • 2Institute of Physics, Slovak Academy of Sciences, Bratislava 84511, Slovakia
  • 3Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
  • 4Laboratori Nazionali del Sud, INFN, via Santa Sofia 62, I-95123 Catania, Italy

  • *Corresponding author: soulioti@chem.uoa.gr

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 92, Iss. 2 — August 2015

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review C

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×