The differential cross sections of $\Lambda_\mathrm{c}^+$ baryon production are measured via the exclusive decay channel $\Lambda_\mathrm{c}^+ \to $pK$^-\pi^+$, as a function of transverse momentum ($p_\mathrm{T}$) in proton-proton (pp) and lead-lead (PbPb) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV with the CMS detector at the LHC. The measurement is performed within the $\Lambda_\mathrm{c}^+$ rapidity interval $|y|<$1.0 in the $p_\mathrm{T}$ range of 5-20 GeV/$c$ in pp and 10-20 GeV/$c$ in PbPb collisions. The observed yields of $\Lambda_\mathrm{c}^+$ for $p_\mathrm{T}$ of 10-20 GeV/$c$ suggest a possible suppression in central PbPb collisions compared to pp collisions. The $\Lambda_\mathrm{c}^+/$D$^0$ production ratio in pp collisions is compared to theoretical models. In PbPb collisions, this ratio is consistent with the result from pp collisions in their common $p_\mathrm{T}$ range.
The $p_{T}$-differential cross sections for inclusive $\Lambda_{c}^{+}$ production in pp collisions. The uncertainties associated with the $\Lambda_{c}^{+} \to pK^{-}\pi^{+}$ branching fraction and subresonant contributions, the luminosity and the nonprompt fraction contribute only to the overall normalization and are labeled global uncertainties ($21\%$).
The $T_{AA}$-scaled yields for inclusive $\Lambda_{c}^{+}$ baryon in three centrality regions of PbPb collisions. The uncertainties associated with the $\Lambda_{c}^{+} \to pK^{-}\pi^{+}$ branching fraction and subresonant contributions, the MB selection efficiency and the nonprompt fraction contribute only to the overall normalization and are labeled global uncertainties ($31\%$).
The nuclear modification factor $R_{AA}$ versus $\langle N_\text{part} \rangle$ for inclusive $\Lambda_{c}^{+}$ production in the centrality range $0-100\%$, $0-30\%$ and $30-100\%$. The systematic uncertainties include the PbPb systematic uncertainties associated with the signal extraction, $p_{T}$ spectrum, selection criteria, track reconstruction, and $T_{AA}$. The pp uncertainty includes the same uncertainties for the pp data (except for $T_{AA}$) plus the uncertainties in pp yield and luminosity. The global PbPb uncertainty includes the uncertainty from the nonprompt fraction(accounting for a partial cancelation between pp and PbPb) and MB selection efficiency.
The transverse momentum spectra of D$^0$ mesons from b hadron decays are measured at midrapidity ($|y|$ $<$ $1$) in pp and PbPb collisions at a nucleon-nucleon center of mass energy of 5.02 TeV with the CMS detector at the LHC. The D$^0$ mesons from b hadron decays are distinguished from prompt D$^0$ mesons by their decay topologies. In PbPb collisions, the B $\to$ D$^0$ yield is found to be suppressed in the measured $p_\mathrm{T}$ range from 2 to 100 GeV$/c$ as compared to pp collisions. The suppression is weaker than that of prompt D$^0$ mesons and charged hadrons for $p_\mathrm{T}$ around 10 GeV$/c$. While theoretical calculations incorporating partonic energy loss in the quark-gluon plasma can successfully describe the measured B $\to$ D$^0$ suppression at higher $p_\mathrm{T}$, the data show an indication of larger suppression than the model predictions in the range of 2 $\lt$ $p_\mathrm{T}$ $\lt$ 5 GeV$/c$.
$ {{{\mathrm {B}}}\to {\mathrm {D^0}}} $ $ {p_{\mathrm {T}}} $ -differential cross section in pp collisions at ${\sqrt {\smash [b]{s}}} = $ 5.02 TeV.
$ {{{\mathrm {B}}}\to {\mathrm {D^0}}} $ $ {p_{\mathrm {T}}} $ -differential invariant yield in PbPb collisions normalized with $ {T_{\mathrm {AA}}} $ at ${\sqrt {\smash [b]{s_{_{\mathrm {NN}}}}}} = $ 5.02 TeV.
The $\text {data}/\mathrm {FONLL}$ ratio for the $ {{{\mathrm {B}}}\to {\mathrm {D^0}}} $ $ {p_{\mathrm {T}}} $ spectra in pp collisions.
The transverse momentum ($p_\mathrm{t}$) spectrum of prompt D$^0$ mesons and their antiparticles has been measured via the hadronic decay channels D$^0 \to \mathrm{K}^- \pi^+$ and $\overline{\mathrm{D}}^0 \to \mathrm{K}^+ \pi^-$ in pp and PbPb collisions at a centre-of-mass energy of 5.02 TeV per nucleon pair with the CMS detector at the LHC. The measurement is performed in the D$^0$ meson $p_\mathrm{t}$ range of 2-100 GeV and in the rapidity range of $|y| < $1. The pp (PbPb) dataset used for this analysis corresponds to an integrated luminosity of 27.4 pb$^{-1}$ (530 $\mu$b$^{-1}$). The measured D$^0$ meson $p_\mathrm{t}$ spectrum in pp collisions is well described by perturbative QCD calculations. The nuclear modification factor, comparing D$^0$ meson yields in PbPb and pp collisions, was extracted for both minimum-bias and the 10% most central PbPb interactions. For central events, the D$^0$ meson yield in the PbPb collisions is suppressed by a factor of 5-6 compared to the pp reference in the $p_\mathrm{t}$ range of 6-10 GeV. For D$^0$ mesons in the high-$p_\mathrm{t}$ range of 60-100 GeV, a significantly smaller suppression is observed. The results are also compared to theoretical calculations.
Nuclear modification factor of $(D^{0}+\overline{D}\hspace{.01cm}^{0})/2$ as a function of $p_{T}$ in the centrality range $0-100\%$ and $0-10\%$.
The $p_{T}$-differential production cross section of $(D^{0}+\overline{D}\hspace{.01cm}^{0})/2$ in pp collisions.
The $p_{T}$-differential production yields of $(D^{0}+\overline{D}\hspace{.01cm}^{0})/2$ divided by the nuclear overlap functions $T_{AA}$ for PbPb collisions in the $0-100\%$ and $0-10\%$ centrality ranges.
The CMS Collaboration presents the first measurement of the differential cross section of jets from charm quarks produced in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of sqrt(s[NN]) = 5.02 TeV, as well as results from charm quark jets in proton-proton (pp) collisions at sqrt(s) = 2.76 and 5.02 TeV. By comparing the yields of the pPb and pp collision systems at the same energy, a nuclear modification factor for charm jets from 55 to 400 GeV/c in pPb collisions at sqrt(s[NN]) = 5.02 TeV of R[pA] = 0.92 +/- 0.07 (stat) +/- 0.11 (syst) is obtained. This is consistent with an absence of final-state energy loss for charm quarks in pPb collisions. In addition, the fraction of jets coming from charm quarks is found to be consistent with that predicted by PYTHIA 6 for pp collisions at sqrt(s)= 2.76 and 5.02 TeV, and is independent of the jet transverse momentum from 55 to 400 GeV/c.
Inclusive charm-jet cross section (and fraction) in pp collisions at 5.02 TeV.
Inclusive charm-jet cross section (and fraction) in pp collisions at 2.76 TeV
Inclusive charm-jet cross section in pp and pPb collisions at 5.02 TeV, with nuclear modification factor RpA for c-jets
The production cross sections of the B+, B0, and B0s mesons, and of their charge conjugates, are measured via exclusive hadronic decays in pPb collisions at the center-of-mass energy sqrt(s_NN) = 5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 inverse nanobarns. The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in PbPb collisions.
The measured $p_{\rm{T}}$-differential production cross section of $B^{+}$ in $p$ + Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV, together with the cross section calculated by the FONLL model.
The measured $p_{\rm{T}}$-differential production cross section of $B^{0}$ in $p$ + Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV, together with the cross section calculated by the FONLL model.
The measured $p_{\rm{T}}$-differential production cross section of $B_{s}^{0}$ in $p$ + Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV, together with the cross section calculated by the FONLL model.
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