A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Charm-quark fragmentation fractions and production cross section at midrapidity in pp collisions at the LHC (2022)

ALICE Collaboration. (2022). Charm-quark fragmentation fractions and production cross section at midrapidity in pp collisions at the LHC. Physical Review D, 105(1), Article L011103. https://doi.org/10.1103/PhysRevD.105.L011103

JYU-tekijät tai -toimittajat

Julkaisun tiedot

Julkaisun kaikki tekijät tai toimittajat: ALICE Collaboration

Lehti tai sarja: Physical Review D

ISSN: 2470-0010

eISSN: 2470-0029

Julkaisuvuosi: 2022

Ilmestymispäivä: 12.01.2022

Volyymi: 105

Lehden numero: 1

Artikkelinumero: L011103

Kustantaja: American Physical Society

Julkaisumaa: Yhdysvallat (USA)

Julkaisun kieli: englanti

DOI: https://doi.org/10.1103/PhysRevD.105.L011103

Julkaisun avoin saatavuus: Avoimesti saatavilla

Julkaisukanavan avoin saatavuus: Osittain avoin julkaisukanava

Julkaisu on rinnakkaistallennettu (JYX): https://jyx.jyu.fi/handle/123456789/80063

Julkaisu on rinnakkaistallennettu: https://arxiv.org/abs/2105.06335

Tiivistelmä

Recent pT-integrated cross-section measurements of the ground-state charm mesons and baryons, D0, D+, Ds+, Λc+, and Ξc0, are used to evaluate the charm fragmentation fractions and production cross section per unit of rapidity at midrapidity (|y|<0.5), in pp collisions at s=5.02 TeV at the LHC. The latter is dσcc¯/dy||y|<0.5=1165±44(stat)-101+134(syst) μb. These measurements were obtained for the first time in hadronic collisions at the LHC, including the charm baryon states, recently measured by ALICE at midrapidity. The charm fragmentation fractions differ significantly from the values measured in e+e- and ep collisions, providing evidence of the dependence of the parton-to-hadron fragmentation fractions on the collision system, indicating that the assumption of their universality is not supported by the measured cross sections. An increase of a factor of about 3.3 for the fragmentation fraction for the Λc+ with a significance of 5σ between the values obtained in pp collisions and those obtained in e+e- (ep) collisions is reported. The fragmentation fraction for the Ξc0 was obtained for the first time in any collision system. The measured fragmentation fractions were used to update the cc¯ cross sections per unit of rapidity at |y|<0.5 at s=2.76 and 7 TeV, which are about 40% higher than the previously published results. The data were compared with perturbative-QCD calculations and lie at the upper edge of the theoretical bands.

YSO-asiasanat: hiukkasfysiikka; kvanttiväridynamiikka

Liittyvät organisaatiot

OKM-raportointi: Kyllä

Raportointivuosi: 2022

Alustava JUFO-taso: 2