A dynamical description of the ¹³⁶ Xe + p spallation at 1000 MeV/nucleon

Abstract

We propose a dynamical description of the 136Xe + p spallation at 1000 MeV/nucleon with the aim of probing the mechanism which rules the production of intermediate-mass fragments (IMF). The isospin-dependent quantum molecular dynamics (IQMD) model is used to describe the dynamical process of spallation until hot fragments with excitation energy less than a certain value Estop are formed. The statistical code GEMINI is applied to simulate the light-particle evaporation from hot fragments. It is found that IMF production is well described by the model when Estop = 2 MeV/nucleon is used. Comparison of the calculated mean neutron-to-proton ratio and the experimental data indicates that Estop should be 3 MeV/nucleon.

Correlation between nuclear temperatures and symmetry energy in sub-saturation

“…We attempt to study the correlation between nuclear temperatures and symmetry energy in a low-density region via the isospin-dependent quantum molecular dynamics (IQMD) model [25][26][27][28] incorporating the statistical decay model GEMINI [29]. To better connect the two models, we needed a dynamical model to describe the intermediate-mass-fragment (IMF) emission.…”

“…In this work, E stop = 2 MeV/nucleon. Using this value, the experimental data for IMF production can be described very well [27].…”

Light fragment and neutron emission in high-energy proton induced spallation reactions

“…In this part, we tried to employ the PSDC method in the reproduction of the IMFs yields, as was previously done in Ref. [35] in which the reproduced IMFs cross-sections in between 5 ≤ Z ≤ 40 agrees with the experimental data to some extent. Our calculation, differing from that of Ref.…”

“…[30][31][32], more sophisticated re-action mechanism beyond the simple two-step model is required in order to account for the production of the Intermediate-Mass-Fragments (IMFs) featured in its experimentally revealed triple-humped kinematics in the velocity distributions [33]. So these features were studied by introducing the deexcitation mode of multifragmentation through Intranuclear-Cascade plus Statistical-Multifragmentation model (INC+SMM) [32] or more inherent models such as the Boltzmann-Langevin-One-Body (BLOB) [34] or the Quantum-Molecular-Dynamics model (QMD) [35]. Moreover, the fermionic properties of nucleons also has an important role to play in the formation of IMFs [36] and thus the beginning part of discussion of this work is related to this area of research.…”

A Bayesian-Neural-Network Prediction for Fragment Production in Proton Induced Spallation Reaction

“…On the theoretical side, many models have been developed. The quantum molecular dynamics model has been improved for spallation reactions, for example, [9][10][11]. The statistical multi-fragmentation model [12][13][14], the Liège intranuclear cascade (incl++) model [15][16][17] (which has been implanted in the openMC, GEANT4 and FLUKA toolkits [18,19]), can be used to simulate the spallation reactions, which are usually followed by a secondary decaying simulation to reproduce the experimental results (A review is also recommended [20]).…”