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Abstract The transverse momentum ($$p_{\textrm{T}}$$ ) differential production cross section of the promptly produced charm-strange baryon$$\mathrm {\Xi _{c}^{0}}$$ (and its charge conjugate$$\overline{\mathrm {\Xi _{c}^{0}}}$$ ) is measured at midrapidity via its hadronic decay into$$\mathrm{\pi ^{+}}\Xi ^{-}$$ in p–Pb collisions at a centre-of-mass energy per nucleon–nucleon collision$$\sqrt{s_{\textrm{NN}}}~=~5.02$$ TeV with the ALICE detector at the LHC. The$$\mathrm {\Xi _{c}^{0}}$$ nuclear modification factor ($$R_{\textrm{pPb}}$$ ), calculated from the cross sections in pp and p–Pb collisions, is presented and compared with the$$R_{\textrm{pPb}}$$ of$$\mathrm {\Lambda _{c}^{+}}$$ baryons. The ratios between the$$p_{\textrm{T}}$$ -differential production cross section of$$\mathrm {\Xi _{c}^{0}}$$ baryons and those of$$\mathrm {D^0}$$ mesons and$$\mathrm {\Lambda _{c}^{+}}$$ baryons are also reported and compared with results at forward and backward rapidity from the LHCb Collaboration. The measurements of the production cross section of prompt$$\Xi ^0_\textrm{c}$$ baryons are compared with a model based on perturbative QCD calculations of charm-quark production cross sections, which includes only cold nuclear matter effects in p–Pb collisions, and underestimates the measurement by a factor of about 50. This discrepancy is reduced when the data is compared with a model that includes string formation beyond leading-colour approximation or in which hadronisation is implemented via quark coalescence. The$$p_{\textrm{T}}$$ -integrated cross section of prompt$$\Xi ^0_\textrm{c}$$ -baryon production at midrapidity extrapolated down to$$p_{\textrm{T}}$$ = 0 is also reported. These measurements offer insights and constraints for theoretical calculations of the hadronisation process. Additionally, they provide inputs for the calculation of the charm production cross section in p–Pb collisions at midrapidity.
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Measurement of non-prompt $${{\textrm{D}}^{0}}$$-meson elliptic flow in Pb–Pb collisions at $$\sqrt{s_{\textrm{NN}}} = 5.02$$ TeV
Abstract The elliptic flow$$(v_2)$$ of$${\textrm{D}}^{0}$$ mesons from beauty-hadron decays (non-prompt$${\textrm{D}}^{0})$$ was measured in midcentral (30–50%) Pb–Pb collisions at a centre-of-mass energy per nucleon pair$$\sqrt{s_{\textrm{NN}}} = 5.02$$ TeV with the ALICE detector at the LHC. The$${\textrm{D}}^{0}$$ mesons were reconstructed at midrapidity$$(|y|<0.8)$$ from their hadronic decay$$\mathrm {D^0 \rightarrow K^-\uppi ^+}$$ , in the transverse momentum interval$$2< p_{\textrm{T}} < 12$$ GeV/c. The result indicates a positive$$v_2$$ for non-prompt$${{\textrm{D}}^{0}}$$ mesons with a significance of 2.7$$\sigma $$ . The non-prompt$${{\textrm{D}}^{0}}$$ -meson$$v_2$$ is lower than that of prompt non-strange D mesons with 3.2$$\sigma $$ significance in$$2< p_\textrm{T} < 8~\textrm{GeV}/c$$ , and compatible with the$$v_2$$ of beauty-decay electrons. Theoretical calculations of beauty-quark transport in a hydrodynamically expanding medium describe the measurement within uncertainties.
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- PAR ID:
- 10514583
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- link.springer.com
- Date Published:
- Journal Name:
- The European Physical Journal C
- Volume:
- 83
- Issue:
- 12
- ISSN:
- 1434-6052
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1140/epjc/s10052-023-12259-3
