Measurement of Prompt D0, Λc+, and Σc 0, ++ (2455) Production in Proton-Proton Collisions at √s = 13 TeV

The ${p}_{T}$-differential production cross sections of prompt ${D}^{0}$, ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$, and ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,++}(2455)$ charmed hadrons are measured at midrapidity ($|y|<0.5$) in $pp$ collisions at $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$. This is the first measurement of ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,++}$ production in hadronic collisions. Assuming the same production yield for the three ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,+,++}$ isospin states, the baryon-to-meson cross section ratios ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,+,++}/{D}^{0}$ and ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}/{D}^{0}$ are calculated in the transverse momentum (${p}_{T}$) intervals $2<{p}_{T}<12$ and $1<{p}_{T}<24\text{ }\mathrm{GeV}/c$. Values significantly larger than in ${e}^{+}{e}^{\ensuremath{-}}$ collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the ${\mathrm{\ensuremath{\Sigma}}}_{c}$. The feed-down contribution to ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ production from ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,+,++}$ is also reported and is found to be larger than in ${e}^{+}{e}^{\ensuremath{-}}$ collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.