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A<sc>bstract</sc> The production yields of the Σ(1385)±and Ξ(1530)0resonances are measured in pp collisions at$$ \sqrt{s} $$ = 13 TeV with ALICE. The measurements are performed as a function of the charged-particle multiplicity ⟨dNch/dη⟩, which is related to the energy density produced in the collision. The results include transverse momentum (pT) distributions,pT-integrated yields, mean transverse momenta of Σ(1385)±and Ξ(1530)0, as well as ratios of thepT-integrated resonance yields relative to yields of other hadron species. The Σ(1385)±/π±and Ξ(1530)0/π±yield ratios are consistent with the trend of the enhancement of strangeness production from low to high multiplicity pp collisions, which was previously observed for strange and multi-strange baryons. The yield ratio between the measured resonances and the long-lived baryons with the same strangeness content exhibits a hint of a mild increasing trend at low multiplicity, despite too large uncertainties to exclude the flat behaviour. The results are compared with predictions from models such as EPOS-LHC and PYTHIA 8 with Rope shoving. The latter provides the best description of the multiplicity dependence of the Σ(1385)±and Ξ(1530)0production in pp collisions at$$ \sqrt{s} $$ = 13 TeV.
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Measurement of the non-prompt D-meson fraction as a function of multiplicity in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV
A<sc>bstract</sc> The fractions of non-prompt (i.e. originating from beauty-hadron decays) D0and D+mesons with respect to the inclusive yield are measured as a function of the charged-particle multiplicity in proton-proton collisions at a centre-of-mass energy of$$ \sqrt{s} $$ = 13 TeV with the ALICE detector at the LHC. The results are reported in intervals of transverse momentum (pT) and integrated in the range 1< pT<24 GeV/c. The fraction of non-prompt D0and D+mesons is found to increase slightly as a function ofpTin all the measured multiplicity intervals, while no significant dependence on the charged-particle multiplicity is observed. In order to investigate the production and hadronisation mechanisms of charm and beauty quarks, the results are compared to PYTHIA 8 as well as EPOS 3 and EPOS 4 Monte Carlo simulations, and to calculations based on the colour glass condensate including three-pomeron fusion.
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- PAR ID:
- 10514847
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- link.springer.com
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2023
- Issue:
- 10
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/JHEP10(2023)092
