Beauty production in pp collisions at $\sqrt{s}$ = 2.76 TeV measured via semi-electronic decays

TL;DR

This paper measures the production cross section of electrons from beauty hadron decays in proton-proton collisions at 2.76 TeV, using ALICE detector data, and compares results with perturbative QCD predictions, providing insights into heavy-flavor production.

Contribution

First measurement of beauty decay electron cross section at 2.76 TeV in pp collisions, using impact parameter and azimuthal correlation methods, with results consistent with QCD calculations.

Findings

Measured integrated cross section: 3.47 μb with uncertainties.

Total b-bbar production cross section: 130 μb with uncertainties.

Results agree with perturbative QCD predictions.

Abstract

The ALICE collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity $|y|<0.8$ and transverse momentum $1<p_{\mathrm{T}}<10$ GeV/$c$, in pp collisions at $\sqrt{s} = $ 2.76 TeV. Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD calculations agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, $\sigma_{\mathrm{b} \rightarrow \mathrm{e}} = 3.47\pm0.40(\mathrm{stat})^{+1.12}_{-1.33}(\mathrm{sys})\pm0.07(\mathrm{norm}) \mu$b, was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) predictions to obtain the total b$\bar{\mathrm{b}}$ production cross section, $\sigma_{\mathrm{b\bar{b}}} = 130\pm15.1(\mathrm{stat})^{+42.1}_{-49.8}(\mathrm{sys})^{+3.4}_{-3.1}(\mathrm{extr})\pm2.5(\mathrm{norm})\pm4.4(\mathrm{BR}) \mu$b.