Probing the momentum-dependent symmetry potential via nuclear collective flows

Abstract

The dependence of the momentum-dependent symmetry potential on the nuclear collective flows produced in semicentral 197 Au + 197 Au collisions at incident energies from 250 to 800A MeV has been investigated within the isospin-dependent quantum molecular dynamics model. It is found that the theoretical results overestimate the values of the experimental data on directed flow of protons in the domain of large rapidities but can reproduce well the one of mass-three cluster. Neutron-proton differential flows and difference of neutron-proton collective flows are sensitive to the momentum-dependent symmetry potential, especially in the domain of larger rapidities and momenta. This sensitivity becomes stronger with increasing cut of the transverse velocity and becomes smaller with increasing incident energies.

Nucleon effective mass splitting and density-dependent symmetry energy effects on elliptic flow in heavy ion collisions at Elab= 0.09 ~ 1.5 GeV/nucleon *

“…This is attributed to nucleons with a smaller effective mass experiencing a larger repulsive force (leading to a stronger elliptic flow) than those with a larger effective mass. This finding is consistent with results from the LQMD model and the microscopic stochastic mean-field (SMF) model, although different forms of momentum-dependent symmetry potentials were used [9, [53][54][55]. However, this is different from the results presented in Refs.…”

Effects of density- and momentum-dependent potentials in Au+Au collisions at intermediate energies

“…The angular brackets stand for the average over all events, and φ is the azimuth with respect to the reaction plane. The free protons are obtained by using a coalescence model, in which nucleons with relative momentum p 0 ≤ 300 MeV and relative distance r 0 ≤ 3.0 fm are coalesced into a cluster [38].…”

Results of the ASY-EOS experiment at GSI: The symmetry energy at suprasaturation density

“…Besides the momentum-dependence of the symmetry potential [16,[62][63][64][65][66], attention has to be paid to the recent observation of short-range correlations [67,68], leading to larger tails of the momentum distributions in symmetric matter than in pure neutron matter and to a reduction of the kinetic part in the parametrization of the symmetry energy [69][70][71]. It will be interesting to incorporate these correlations in transport models and to explore their consequences [72,73].…”