Event activity correlations and jet measurements in p+Au collisions at $\sqrt{s_\mathrm{NN}}$ = 200 GeV

The STAR collaboration
2024.

Abstract
With the STAR experiment at RHIC, we characterize $\sqrt{s_\mathrm{NN}}$ = 200 GeV $p$+Au collisions by event activity (EA) measured within the pseudorapidity range $\eta\in[-5,-3.4]$ in the Au-going direction and report correlations between this EA and hard- and soft-scale particle production at mid-rapidity ($\eta\in[-1,1]$). At the soft scale, charged particle production in low-EA $p$+Au collisions is comparable to that in \pp collisions and increases monotonically with increasing EA. At the hard scale, we report measurements of high transverse momentum ($p_\mathrm{T}$) jets in events of different EAs. In contrast to the soft particle production, high-$p_\mathrm{T}$ particle production and EA are found to be inversely related. To investigate whether this is a signal of jet quenching in high-EA events, we also report ratios of $p_\mathrm{T}$ imbalance and azimuthal separation of dijets in high- and low-EA events. Within our measurement precision, no significant differences are observed, disfavoring the presence of jet quenching in the highest 30% EA $p$+Au collisions at $\sqrt{s_\mathrm{NN}}$ = 200 GeV.

Loading Data...