Measurement of the production cross section of prompt Ξc0 baryons in p-Pb collisions at √sNN=5.02 TeV

Abstract

The transverse momentum ( p(T)) differential production cross section of the promptly produced charmstrange baryon Xi(0)(c) (and its charge conjugate ) is measured at midrapidity via its hadronic decay into pi(+)Xi(-) in p-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision root s(NN) = 5.02 TeV with the ALICE detector at the LHC. The Xi(0)(c) nuclear modification factor ( R-pPb), calculated from the cross sections in pp and p-Pb collisions, is presented and compared with the RpPb of Lambda(+)(c) baryons. The ratios between the p(T)-differential production cross section of Xi(0)(c) baryons and those of D-0 mesons and Lambda(+)(c) baryons are also reported and compared with results at forward and backward rapidity from the LHCb Collaboration. Themeasurements of the production cross section of prompt Xi(0)(c) baryons are compared with a model based on perturbative QCD calculations of charm-quark production cross sections, which includes only cold nuclear matter effects in p-Pb collisions, and underestimates the measurement by a factor of about 50. This discrepancy is reduced when the data is compared with a model that includes string formation beyond leading-colour approximation or in which hadronisation is implemented via quark coalescence. The p(T)-integrated cross section of prompt Xi(0)(c)-baryon production at midrapidity extrapolated down to p(T) = 0 is also reported. These measurements offer insights and constraints for theoretical calculations of the hadronisation process. Additionally, they provide inputs for the calculation of the charm production cross section in p-Pb collisions at midrapidity.