High order cumulants of the azimuthal anisotropy in the dilute-dense limit: Connected graphs

Abstract

We analytically compute higher order cumulants of the azimuthal anisotropy, $c_2\{2m\}$, and corresponding $v_2\{2m\}$ at high transverse momentum in the dilute-dense limit. The dense target is considered in the framework of the McLerran-Venugopolan model. The absolute values of the harmonics $v_2\{2m\}$ of the azimuthal anisotropy are approximately equal, $|v_2\{2m\}|\approx |v_2\{2m^{\prime }\}|$, for large $m$ and $m^{\prime }$. However, the harmonics with order $2m=4n$ are complex. We argue that this is a generic property of connected graphs, which remains true in the dense-dense limit.

Comments: 7 pages, 3 figures; version accepted to Phys. Rev. D