Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies

Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Dragicevic, M.; Erö, J.; Escalante Del Valle, A.; Flechl, M.; Frühwirth, R.; Caminada, L.; Deiters, K.; Erdmann, W.; Horisberger, R.; Ingram, Q.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Rohe, T.; Trembath-reichert, S.

doi:10.1016/j.physletb.2020.136036

Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Erö J, Escalante Del Valle A, Flechl M, Frühwirth R, Caminada L, Deiters K, Erdmann W, Horisberger R, Ingram Q, Kaestli HC, Kotlinski D, Langenegger U, Rohe T, Trembath-reichert S, et al.

Citation

Sirunyan, A. M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Dragicevic, M., … Trembath-reichert, S. (2021). Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 813, 136036 (25 pp.). https://doi.org/10.1016/j.physletb.2020.136036

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:36852

Measurements of the second Fourier harmonic coefficient (v₂) of the azimuthal distributions of prompt and nonprompt D⁰ mesons produced in pp and pPb collisions are presented. Nonprompt D⁰ mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, v₂ signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum (p_T) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D⁰ meson v₂ values in pp and pPb collisions are similar in magnitude. The v₂ values for open beauty hadrons are extracted for the first time via nonprompt D⁰ mesons in pPb collisions. For p_T in the range of 2-5 GeV, the results suggest that v₂ for nonprompt D⁰ mesons is smaller than that for prompt D⁰ mesons. These new measurements indicate a positive charm hadron v₂ in pp collisions and suggest a mass dependence in v₂ between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems.