The distribution of angular correlations between prompt charm hadrons and primary charged particles in pp collisions is sensitive to the charm-quark hadronisation process. In this letter, charm-baryon correlations are measured for the first time by studying the azimuthal-angle difference between charged particles and prompt Λc+ baryons produced in pp collisions at a centre-of-mass energy of s=13 TeV, with the ALICE detector. Λc+ baryons are reconstructed at midrapidity (|y|<0.5) in the transverse-momentum interval 3<16 GeV/c, and correlated with charged particles with pT>0.3 GeV/c and pseudorapidity |η|<0.8. For 3<5 GeV/c, the comparison with published measurements of D-meson and charged-particle correlations in the same collision system hints at a larger number of low-momentum particles associated with Λc+-baryon triggers than with D-meson triggers, both in the collinear and opposite directions with respect to the trigger particle. These differences can be quantified by the comparison of the properties of the near- and away-side correlation peaks, and are not reproduced by predictions of various Monte Carlo event generators, generally underpredicting the associated particle yields at pTassoc<1 GeV/c. This tension between Λc+-baryon and D-meson associated peak yields could suggest a modified fragmentation of the charm quark, or a different hadronisation process, when a charm baryon is produced in the final state.

Studying charm hadronisation into baryons with azimuthal correlations of Λc+ with charged particles in pp collisions at s=13 TeV

Caliva, A.;De Caro, A.;De Gruttola, D.;De Pasquale, S.;Funicello, N.;Pucillo, S.;Ripoli, C.;Virgili, T.;
2025

Abstract

The distribution of angular correlations between prompt charm hadrons and primary charged particles in pp collisions is sensitive to the charm-quark hadronisation process. In this letter, charm-baryon correlations are measured for the first time by studying the azimuthal-angle difference between charged particles and prompt Λc+ baryons produced in pp collisions at a centre-of-mass energy of s=13 TeV, with the ALICE detector. Λc+ baryons are reconstructed at midrapidity (|y|<0.5) in the transverse-momentum interval 3<16 GeV/c, and correlated with charged particles with pT>0.3 GeV/c and pseudorapidity |η|<0.8. For 3<5 GeV/c, the comparison with published measurements of D-meson and charged-particle correlations in the same collision system hints at a larger number of low-momentum particles associated with Λc+-baryon triggers than with D-meson triggers, both in the collinear and opposite directions with respect to the trigger particle. These differences can be quantified by the comparison of the properties of the near- and away-side correlation peaks, and are not reproduced by predictions of various Monte Carlo event generators, generally underpredicting the associated particle yields at pTassoc<1 GeV/c. This tension between Λc+-baryon and D-meson associated peak yields could suggest a modified fragmentation of the charm quark, or a different hadronisation process, when a charm baryon is produced in the final state.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11386/4919976
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact