Elliptic flow from minijet production in heavy ion collisions

Abstract

We calculate the contribution to the elliptic flow observable v 2 from two-particle correlations in minijet production in ultrarelativistic heavy ion collisions. We use a minijet production cross section derived in a model inspired by saturation approach to high energy scattering. Resulting differential elliptic flow v 2 (p T ) is an increasing function of p T for transverse momenta below the saturation scale Q s . At higher transverse momenta (p T > Q s ) differential flow stops growing and becomes approximately constant, reproducing the elliptic flow saturation data reported by STAR. The centrality dependence of the minijet contribution to v 2 is also in good agreement with the data.

Rapidity and centrality dependence of azimuthal correlations in deuteron–Gold collisions at RHIC

“…We calculated the azimuthal correlation function in dAu collisions using the approach developed by us before [7,8]. The results are presented in Figs.…”

“…On the other hand, k T -factorization is known to give results that are in qualitative agreement with a more accurate approaches, but misses the overall normalization. Therefore, in order to correct the overall normalization of the cross sections we multiply the single inclusive cross section (4) by a constant K 1 and the doubleinclusive one (7) by a different constant K 2 [7]. The correlation function C depends on both K 1 and K 2 .…”

Initial state angular asymmetries in high energy p+A collisions: Spontaneous breaking of rotational symmetry by a color electric field and C-odd fluctuations

“…The quadrupole moment v 2 in the initial state of high-energy collisions has been first calculated by Kovchegov and Tuchin long ago [11]. Non-zero v 2 emerges due to the fact that the two-gluon production cross section at relative angle φ 1 − φ 2 ∼ 0, π is enhanced, while it is suppressed for φ 1 − φ 2 ∼ ±π/2.…”

Saturation of Azimuthal Anisotropy in Au+Au Collisions at sNN=62–200 GeV

“…They provide important constraints for the density of the medium and the effective energy loss of partons which traverse it [9,10]. They can provide valuable information on the gluon saturation scale in the nucleus [11].…”