Three-particle cumulant Study of Conical Emission

TL;DR

This paper evaluates the effectiveness of the three-particle azimuthal cumulant method in detecting conical emission in relativistic heavy-ion collisions, considering various background effects and flow harmonics.

Contribution

It provides a detailed analysis of the sensitivity of cumulant methods for conical emission detection, highlighting limitations and the impact of flow harmonics and background.

Findings

Conical emission detection is hindered by fourth-order flow harmonics but still feasible.

Probability cumulants reduce second-order flow contributions but complicate jet and conical signals.

Sensitivity depends on flow harmonics, background, and particle production characteristics.

Abstract

We discuss the sensitivity of the three-particle azimuthal cumulant method for a search and study of conical emission in central relativistic $A+A $ collisions. Our study is based on a multi-component Monte Carlo model which include flow background, Gaussian mono-jets, jet-flow, and Gaussian conical signals. We find the observation of conical emission is hindered by the presence of flow harmonics of fourth order ($v_4 $) but remains feasible even in the presence of a substantial background. We consider the use of probability cumulants for the suppression of 2$^{nd}$ order flow harmonics. We find that while probability cumulant significantly reduce $v_2^2$ contributions, they also complicate the cumulant of jets, and conical emission. The use of probability cumulants is therefore not particularly advantageous in searches for conical emission. We find the sensitivity of the (density) cumulant method depends inextricably on strengths of $v_2 $, $v_4 $, background and non-Poisson character of particle production. It thus cannot be expressed in a simple form, and without specific assumptions about the values of these parameters.