First measurement of $\rm \Omega_c^0$ production in pp collisions at $\sqrt{s}=13$ TeV

TL;DR

This paper reports the first measurement of $ m Omega_c^0$ production in proton-proton collisions at 13 TeV, providing new data on charm baryon production and hadronisation mechanisms at high energies.

Contribution

It presents the first measurement of $ m Omega_c^0$ production cross section in pp collisions at 13 TeV, comparing it to models and other charm baryons.

Findings

The $ m Omega_c^0$ production ratio to $ m Lambda_c^+$ is about 20 times higher than in $e^+e^-$ collisions.

The $p_T$-differential cross section for $ m Omega_c^0$ is measured between 2 and 12 GeV/c.

The results challenge existing hadronisation models and provide new constraints.

Abstract

The inclusive production of the charm-strange baryon $\rm \Omega_c^0$ is measured for the first time via its hadronic decay into $\rm \Omega^-\pi^+$ at midrapidity ($|y|<0.5$) in proton-proton (pp) collisions at the centre-of-mass energy $\sqrt{s}=13$ TeV with the ALICE detector at the LHC. The transverse momentum ($p_{\rm T}$) differential cross section multiplied by the branching ratio is presented in the interval $2<p_{\rm T}<12~{\rm GeV}/c$. The $p_{\rm T}$ dependence of the $\rm \Omega_c^0$-baryon production relative to the prompt $\rm D^0$-meson and to the prompt $\rm \Xi_c^0$-baryon production is compared to various models that take different hadronisation mechanisms into consideration. In the measured $p_{\rm T}$ interval, the ratio of the $p_{\rm T}$-integrated cross sections of $\rm \Omega_c^0$ and prompt $\Lambda_{\rm c}^{+}$ baryons multiplied by the $\rm \Omega^-\pi^+$ branching ratio is found to be larger by a factor of about 20 with a significance of about 4$\sigma$ when compared to $\rm e^+e^-$ collisions.