Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV

Abstract

The ALICE experiment at the LHC has studied J/ψ production at midrapidity in pp collisions at √s = 7TeV through its electron pair decay on a data sample corresponding to an integrated luminosity Lint = 5.6 nb−1. The fraction of J/ψ from the decay of long-lived beauty hadrons was determined for J/ψ candidates with transverse momentum pt > 1.3GeV/c and rapidity |y| < 0.9. The cross section for prompt J/ψ mesons, i.e. directly produced J/ψ and prompt decays of heavier charmonium states such as the ψ(2S) and χc resonances, is σprompt J/ψ (pt > 1.3 GeV/c, |y| < 0.9) = 8.3±0.8 (stat.) ± 1.1 (syst.) +1.5−1.4 (syst. pol.) μb. The cross section for the production of b-hadrons decaying to J/ψ with pt > 1.3GeV/c and |y| < 0.9 is σJ/ψ←hB (pt > 1.3 GeV/c, |y| < 0.9) = 1.46 ± 0.38 (stat.) +0.26−0.32 (syst.) μb. The results are compared to QCD model predictions. The shape of the pt and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the bb pair total cross section and dσ/dy at mid-rapidity.


Autore Pugliese

Tutti gli autori

  • FIORE E.M.;BRUNO G.E.

Titolo volume/Rivista

Non Disponibile


Anno di pubblicazione

2012

ISSN

Non Disponibile

ISBN

Non Disponibile


Numero di citazioni Wos

24

Ultimo Aggiornamento Citazioni

Non Disponibile


Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

Non Disponibile


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile