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A<sc>bstract</sc> The production of prompt$$ {\Lambda}_{\textrm{c}}^{+} $$ baryons is measured via the exclusive decay channel$$ {\Lambda}_{\textrm{c}}^{+}\to p{\textrm{K}}^{-}{\pi}^{+} $$ at a center-of-mass energy per nucleon pair of 5.02 TeV, using proton-proton (pp) and lead-lead (PbPb) collision data collected by the CMS experiment at the CERN LHC. The pp and PbPb data were obtained in 2017 and 2018 with integrated luminosities of 252 and 0.607 nb−1, respectively. The measurements are performed within the$$ {\Lambda}_{\textrm{c}}^{+} $$ rapidity interval |y|<1 with transverse momentum (pT) ranges of 3–30 and 6–40 GeV/cfor pp and PbPb collisions, respectively. Compared to the yields in pp collisions scaled by the expected number of nucleon-nucleon interactions, the observed yields of$$ {\Lambda}_{\textrm{c}}^{+} $$ withpT>10 GeV/care strongly suppressed in PbPb collisions. The level of suppression depends significantly on the collision centrality. The$$ {\Lambda}_{\textrm{c}}^{+} $$ /D0production ratio is similar in PbPb and pp collisions atpT>10 GeV/c, suggesting that the coalescence process does not play a dominant role in prompt$$ {\Lambda}_{\textrm{c}}^{+} $$ baryon production at higherpT.
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This content will become publicly available on November 1, 2025
Measurement of beauty production via non-prompt charm hadrons in p–Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV
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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- PAR ID:
- 10599257
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2024
- Issue:
- 11
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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