# Measurements of $\mu \mu$ pairs from open heavy flavor and Drell-Yan in $p+p$ collisions at $\sqrt{s}=200\text{}\text{}\mathrm{GeV}$

10 April 2019

Abstract: PHENIX reports differential cross sections of $\mu \mu$ pairs from semileptonic heavy-flavor decays and the Drell-Yan production mechanism measured in $p+p$ collisions at $\sqrt{s}=200\text{}\text{}\mathrm{GeV}$ at forward and backward rapidity ($1.2<|\eta |<2.2$). The $\mu \mu$ pairs from $c\overline{c}$, $b\overline{b}$, and Drell-Yan are separated using a template fit to unlike- and like-sign muon pair spectra in mass and ${p}_{T}$. The azimuthal opening angle correlation between the muons from $c\overline{c}$ and $b\overline{b}$ decays and the pair-${p}_{T}$ distributions are compared to distributions generated using pythia and powheg models, which both include next-to-leading order processes. The measured distributions for pairs from $c\overline{c}$ are consistent with pythia calculations. The $c\overline{c}$ data present narrower azimuthal correlations and softer ${p}_{T}$ distributions compared to distributions generated from powheg. The $b\overline{b}$ data are well described by both models. The extrapolated total cross section for bottom production is $3.75±0.24\left(\mathrm{stat}\right){±}_{0.50}^{0.35}\left(\mathrm{syst}\right)±0.45\left(\text{global}\right)\text{}\text{}\left[\mu b\right]$, which is consistent with previous measurements at the Relativistic Heavy Ion Collider in the same system at the same collision energy and is approximately a factor of 2 higher than the central value calculated with theoretical models. The measured Drell-Yan cross section is in good agreement with next-to-leading-order quantum-chromodynamics calculations.

Published in: Physical Review D 99 (2019)