On the rapidity dependence of the average transverse momentum in hadronic collisions

TL;DR

This paper investigates how the average transverse momentum varies with rapidity in proton-proton and proton-nucleus collisions at RHIC and LHC energies, using the Colour Glass Condensate formalism and phenomenological models.

Contribution

It updates predictions for transverse momentum spectra within the CGC framework and demonstrates model agreement with experimental data, providing new insights into rapidity dependence.

Findings

Models describe RHIC and LHC data for $p_T \,\le 20$ GeV.

The ratio of average transverse momentum decreases with rapidity.

Predictions align with hydrodynamical behavior.

Abstract

The energy and rapidity dependence of the average transverse momentum $\langle p_T \rangle$ in $pp$ and $pA$ collisions at RHIC and LHC energies are estimated using the Colour Glass Condensate (CGC) formalism. We update previous predictions for the $p_T$ - spectra using the hybrid formalism of the CGC approach and two phenomenological models for the dipole - target scattering amplitude. We demonstrate that these models are able to describe the RHIC and LHC data for the hadron production in $pp$, $dAu$ and $pPb$ collisions at $p_T \le 20$ GeV. Moreover, we present our predictions for $\langle p_T \rangle$ and demonstrate that the ratio $\langle p_{T}(y)\rangle / \langle p_{T}(y = 0)\rangle$ decreases with the rapidity and has a behaviour similar to that predicted by hydrodynamical calculations.