XXVIII International Workshop on Deep-Inelastic Scattering and Related Subjects

Correlations between azimuthal asymmetries and multiplicity and mean transverse momentum in small collisions systems in the CGC

14 Apr 2021, 08:54

18m

Virtual (Stony Brook, NY)

Contributed Talk Small-x, Diffraction and Vector Mesons Small-x, Diffraction and Vector Mesons

Speaker

Nestor Armesto (Universidade de Santiago de Compostela)

Description

The ridge phenomenon found in high multiplicity pp and pPb collisions is one of the most important observations at the LHC. In such small systems, final state explanations become challenging. We study particle correlations in the Color Glass Condensate, which offers a weak coupling but non perturbative framework to study how correlations in the wave function of the incoming hadrons reflect on those in the final state. Considering a dilute-dense situation suitable for pA collisions, we compute the correlation between azimuthal asymmetries, specifically the squared second Fourier coefficient $v_2^2$, and the total multiplicity in the event. We also consider the correlation between $v_2^2$ and the mean squared transverse momentum of particles in the event. In both cases, we find that the correlations are generally very small, consistent with the observations. We also note an interesting sharp change in the value of $v_2^2$ and its correlations as a function of the width of the transverse momentum bin, related with a change of the dominance of Bose and HBT quantum correlations.

Reference: Tolga Altinoluk, Néstor Armesto, Alex Kovner, Michael Lublinsky and Vladimir V. Skokov, e-Print: 2012.01810 [hep-ph].

Presentation materials

Armesto_DIS2021.pdf

Youtube Link