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

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 نشر من قبل Jianhui Zhu
 تاريخ النشر 2021
  مجال البحث
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 تأليف Jianhui Zhu




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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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