Directed and elliptic flow using neutron rich Sn + Sn collisions with 270MeV/u

Rapidity dependence of directed flow v₁ and elliptic flow v₂ were analyzed for various particles, including proton, deuteron, triton, ³He, and ⁴He.

The experiment was performed by SpiRIT-TPC with wide acceptance at SAMURAI in RIKEN-RIBF.

Using radioactive ion beams, ¹³²Sn+¹²⁴Sn and ¹⁰⁸Sn+¹¹²Sn collisions at 270 MeV/u were utilized to study system dependence with different isospin asymmetries and a common total charge.

To understand the experimental data, we compared them with AMD calculations which explicitly consider the cluster correlation.

Two types of momentum-dependent mean field potential were utilized.

AMD calculations explain the tendency of mass dependence but cannot describe all particles simultaneously.

The sensitivity to the density dependence of the symmetry energy and the system dependence are also discussed.

At last, the newly proposed flow analysis method will be discussed.