J-\psi Production via \chi_c Decays in 920 GeV pA Interactions

TL;DR

This paper reports a measurement of the fraction of J/ψ particles produced via chi_c decays in high-energy proton-nucleus collisions, providing data that supports existing theoretical models.

Contribution

First measurement of the chi_c decay contribution to J/ψ production in 920 GeV pA interactions, with results consistent with prior experiments and theoretical expectations.

Findings

Measured R_{chi_c} = 0.32 ± 0.06_{stat} ± 0.04_{sys}

Results agree with previous measurements

Data compared with theoretical predictions

Abstract

Using data collected by the HERA-B experiment, we have measured the fraction of J\psi's produced via radiative chi_c decays in interactions of 920 GeV protons with carbon and titanium targets. We obtained R_{\chi_c} = 0.32 \pm 0.06_{stat} \pm 0.04_{sys} for the fraction of J\psi from chi_c decays averaged over proton-carbon and proton-titanium collisions. This result is in agreement with previous measurements and is compared with theoretical predictions.