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A<sc>bstract</sc> The production cross sections of D0, D+, and$$ {\Lambda}_{\textrm{c}}^{+} $$ hadrons originating from beauty-hadron decays (i.e. non-prompt) were measured for the first time at midrapidity in proton–lead (p–Pb) collisions at the center-of-mass energy per nucleon pair of$$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV. Nuclear modification factors (RpPb) of non-prompt D0, D+, and$$ {\Lambda}_{\textrm{c}}^{+} $$ are calculated as a function of the transverse momentum (pT) to investigate the modification of the momentum spectra measured in p–Pb collisions with respect to those measured in proton–proton (pp) collisions at the same energy. TheRpPbmeasurements are compatible with unity and with the measurements in the prompt charm sector, and do not show a significantpTdependence. ThepT-integrated cross sections andpT-integratedRpPbof non-prompt D0and D+mesons are also computed by extrapolating the visible cross sections down topT= 0. The non-prompt D-mesonRpPbintegrated overpTis compatible with unity and with model calculations implementing modification of the parton distribution functions of nucleons bound in nuclei with respect to free nucleons. The non-prompt$$ {\Lambda}_{\textrm{c}}^{+} $$ /D0and D+/D0production ratios are computed to investigate hadronisation mechanisms of beauty quarks into mesons and baryons. The measured ratios as a function ofpTdisplay a similar trend to that measured for charm hadrons in the same collision system.
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Prompt and non-prompt J/ψ production at midrapidity in Pb–Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV
A<sc>bstract</sc> The transverse momentum (pT) and centrality dependence of the nuclear modification factorRAAof prompt and non-prompt J/ψ, the latter originating from the weak decays of beauty hadrons, have been measured by the ALICE collaboration in Pb–Pb collisions at$$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV. The measurements are carried out through the e+e−decay channel at midrapidity (|y| < 0.9) in the transverse momentum region 1.5 <pT< 10 GeV/c. Both prompt and non-prompt J/ψmeasurements indicate a significant suppression forpT> 5 GeV/c, which becomes stronger with increasing collision centrality. The results are consistent with similar LHC measurements in the overlappingpTintervals, and cover the kinematic region down topT= 1.5 GeV/cat midrapidity, not accessible by other LHC experiments. The suppression of prompt J/ψin central and semicentral collisions exhibits a decreasing trend towards lower transverse momentum, described within uncertainties by models implementing J/ψproduction from recombination of c and$$ \overline{\textrm{c}} $$ quarks produced independently in different partonic scatterings. At high transverse momentum, transport models including quarkonium dissociation are able to describe the suppression for prompt J/ψ. For non-prompt J/ψ, the suppression predicted by models including both collisional and radiative processes for the computation of the beauty-quark energy loss inside the quark-gluon plasma is consistent with measurements within uncertainties.
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- PAR ID:
- 10514251
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- ink.springer.com
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2024
- Issue:
- 2
- 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/JHEP02(2024)066
