Cross section for $b\bar{b}$ production via dielectrons in d$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV

TL;DR

This paper measures the production cross section of bottom quark pairs in deuteron-gold collisions at 200 GeV by analyzing dielectron pairs from heavy-flavor decays, distinguishing bottom from charm contributions.

Contribution

It provides the first measurement of $b\bar{b}$ production cross section in $d$+Au collisions at 200 GeV, using dielectron decay channels and comparison with simulations.

Findings

Measured $b\bar{b}$ cross section: 1.37 ± 0.28 (stat) ± 0.46 (syst) mb.

Derived nucleon-nucleon $b\bar{b}$ cross section: 3.4 ± 0.8 (stat) ± 1.1 (syst) μb.

Isolated bottom decay contribution from dielectron mass and momentum dependence.

Abstract

We report a measurement of $e^+e^-$ pairs from semileptonic heavy-flavor decays in $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. Exploring the mass and transverse-momentum dependence of the yield, the bottom decay contribution can be isolated from charm, and quantified by comparison to {\sc pythia} and {\sc mc@nlo} simulations. The resulting $b\bar{b}$-production cross section is $\sigma^{d{\rm Au}}_{b\bar{b}}=1.37{\pm}0.28({\rm stat}){\pm}0.46({\rm syst})$~mb, which is equivalent to a nucleon-nucleon cross section of $\sigma^{NN}_{bb}=3.4\pm0.8({\rm stat}){\pm}1.1({\rm syst})\ \mu$b.