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arXiv · 2109.04326

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

Abstract

Recent measurements of charm-baryon production in proton--proton (pp) collisions at midrapidity by the ALICE collaboration showed that baryon-to-meson yield ratios are significantly higher than those measured in $\rm e^+e^-$ collisions. The charm baryon-to-meson and charm baryon-to-baryon yield ratios provide unique information on hadronization mechanisms since the contributions from parton distribution function and parton--parton scattering terms cancel in the ratios. In this contribution, the first measurement of $\rm \Omega_{c}^{0}$ production via the hadronic decay channel $\rm \Omega_{c}^{0} \rightarrow \Omega^{-}\pi^{+}$ (and its charge conjugate) in $2<p_{\rm T}<12$ GeV/$c$ performed with the ALICE detector at midrapidity in pp collisions at $\sqrt{s}=$ 13 TeV is presented. The $\rm \Omega_c^0/D^0$ and $\rm \Omega_c^0/\Xi_c^0$ ratios multiplied by the decay branching ratio $\rm BR(\Omega_{c}^{0} \rightarrow \Omega^{-}\pi^+)$, which is not experimentally measured, are compared to MC generators with fragmentation fractions based on $\rm e^+e^-$ measurements and models including hadronization of charm quark via coalescence.

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Jianhui Zhu. 2021-09-09. First measurement of $\rm \Omega_c^0$ production in pp collisions at $\sqrt{s}=13$ TeV with ALICE. https://arxiv.org/abs/2109.04326

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