Hyperon Global Polarization in Nucleus-Nucleus Collisions at sub-10-GeV Beam Energy

Λ̄–hyperon global polarization in Au+Au collisions at RHIC

We present the Λ̄–hyperon global polarization in Au+Au collisions at √ sNN = 62 GeV and 200 GeV measured with the STAR detector at RHIC. The observed Λ̄–hyperon global polarization is consistent with zero, what is in agreement with recent measurements of Λ global polarization, as well as φ(1020) and K(892) vector mesons spin alignment with respect to the reaction plane. The possible dependence of...

Anisotropy in High Energy Nucleus - Nucleus Collisions

The predictions of event anisotropy parameters from transport model RQMD are compared with the recent experimental measurements for 158A GeV Pb+Pb collisions. Using the same model, we study the time evolution of event anisotropy at 2A GeV and 158A GeV for several colliding systems. For the first time, both momentum and configuration space information are studied using the Fourier analysis of th...

High energy factorization in nucleus-nucleus collisions

We derive a high energy factorization theorem for inclusive gluon production in A+A collisions. Our factorized formula resums i) all order leading logarithms (g ln(1/x1,2)) n of the incoming partons momentum fractions, and ii) all contributions (gρ1,2) n that are enhanced when the color charge densities in the two nuclei are of order of the inverse coupling– ρ1,2 ∼ g . The resummed inclusive gl...

Global Properties of Nucleus-Nucleus Collisions

Nucleus - nucleus collisions at high baryon densities

We study central collision of P b + P b at 20, 40, 80 and 160 A·GeV within the UrQMD transport approach and compare rapidity distributions of π − , K + , K − and Λ with the recent measurements from the NA49 Collaboration at 40, 80 and 160 A·GeV. It is found that the UrQMD model reasonably describes the data, however, systematically overpredicts the π − yield by ∼ 20%, whereas the K + yield is u...