Measurement of the $$ {\Lambda}_c^{+} $$ to D0 production ratio in peripheral PbPb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV

Abstract

We report on a measurement of the $$ {\Lambda}_c^{+} $$ Λ c + to D0 production ratio in peripheral PbPb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ s NN = 5.02 TeV with the LHCb detector in the forward rapidity region 2 < y < 4.5. The $$ {\Lambda}_c^{+} $$ Λ c + (D0) hadrons are reconstructed via the decay channel $$ {\Lambda}_c^{+} $$ Λ c + → pK−π+ (D0→ K−π+) for 2 < pT< 8 GeV/c and in the centrality range of about 65–90%. The results show no significant dependence on pT, y or the mean number of participating nucleons. They are also consistent with similar measurements obtained by the LHCb collaboration in pPb and Pbp collisions at $$ \sqrt{s_{\textrm{NN}}} $$ s NN = 5.02 TeV. The data agree well with predictions from PYTHIA in pp collisions at $$ \sqrt{s} $$ s = 5 TeV but are in tension with predictions of the Statistical Hadronization model.

Hadronization mechanism (via heavy-flavor hadrons): Experiment

“…While, as discussed in the previous section, the 𝑝 T -integrated Λ + c /D 0 ratio does not change significantly from pp to Pb-Pb collisions, it evolves substantially as a function of 𝑝 T with increasing centrality, as shown in Fig. 7 (left panel), where the Pb-Pb ALICE [46], CMS [43], and LHCb [53] results are reported and compared to ALICE pp data as well as to the measurement in Au-Au by STAR [50]. At 𝑝 T > 20 GeV/𝑐 the ratio is consistent with that in e + e − collisions.…”

Modification of heavy quark hadronization in high-multiplicity collisions at LHCb

“…The cross-sections ratios 𝐷 + 𝑠 /𝐷 + results from LHCb collaboration are consistent with the results from ALICE collaboration in 𝑝Pb [6] collisions and in 𝑝 𝑝 [7] collisions within error. This LHCb measurement [8] shows the cross-sections ratio Λ + 𝑐 /𝐷 0 in peripheral PbPb collisions at √ 𝑠 NN = 5.02 TeV. The data sample used to calculate Λ + 𝑐 /𝐷 0 is selected by 1000 < 𝑁 𝑐 < 10000 which 𝑁 𝑐 is the number of clusters in VELO detector.…”

Heavy flavors and quarkonia: highlights, open questions, and perspectives

“…In the left panel of Fig. 4, the evolution of the 𝑝 T -differential Λ + c /D 0 is shown, by comparing the measurements performed in minimum-bias pp collisions, and in different centralities in Pb-Pb collisions at the LHC [13][14][15].…”