title: Mass hierarchy in identified particle distributions in proton-lead collisions.
abstract: We study the mass dependence for identified particle average transverse momentum and harmonic flow coefficients in proton-lead (p-Pb) collisions, recently measured at the LHC. The collective mechanism in the p-Pb system predicts a specific mass ordering in these observables: the growth of the average transverse momentum with the particle mass and a mass splitting of the elliptic flow coefficient, i.e., smaller differential elliptic flow of protons than pions for p(T)<2 GeV. This provides an opportunity to distinguish between the collective scenario and the mechanism based on the initial gluon dynamics in the evolution of the p-Pb system.
authors.affiliation: AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Aleja Mickiewicza 30, 30-059 Krakow, Poland and The H. Niewodniczański Institute of Nuclear Physics PAN, 31-342 Kraków, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Bożek
authors.forename: Wojciech
authors.initials: W
authors.lastname: Broniowski
authors.forename: Giorgio
authors.initials: G
authors.lastname: Torrieri