BAMPS with the improved Gunion-Bertsch matrix element

Focusing on the simultaneous investigation of the hard and the soft regime of ultra-relativistic heavy-ion collisions at the Relativistic Heavy-Ion Collider (RHIC) at the Brookhaven National Laboratory (BNL) and the Large Hadron Collider (LHC) at CERN, we present our recent results on the nuclear modification factor RAA and the elliptic flow v2 within the partonic transport model BAMPS (Boltzmann Approach to Multi-Parton Scatterings). While using interactions provided by perturbative QCD, BAMPS allows the full 3+1D simulation of the quark-gluon plasma (QGP) at the microscopic level by solving the relativistic Boltzmann equation for quarks and gluons. The microscopic interactions include both elastic 2→2 collisions, calculated by screened leading order pQCD matrix elements, and inelastic 2↔3 processes, calculated within an improved Gunion-Bertsch approximation. Furthermore, for all partonic processes a microscopic, running coupling is explicitly taken into account. We show that when fixing the parameter XLPM resulting from the effective modeling of the Landau-Pomeranchuk-Migdal effect, we find not only a good description of RAA at both RHIC and LHC, but also a sizable elliptic flow is built up within the partonic phase.