ϕ and Ω production in relativistic heavy-ion collisions in a dynamical quark coalescence model

Abstract

Based on the phase-space information obtained from a multiphase transport model within the string-melting scenario for strange and antistrange quarks, we study the yields and transverse-momentum spectra of φ mesons and ( − +¯ + ) baryons and their anisotropic flows in Au + Au collisions at RHIC using a dynamical quark coalescence model that includes the effect from quark phase-space distributions inside hadrons. With current quark masses and fixing the φ and radii from fitting measured yields, we first study the ratio of the yield of baryons to that of φ mesons as well as their elliptic and fourth-order flows as functions of their transverse momentum. How the elliptic and fourth-order flows of φ mesons and baryons are related to those of strange and antistrange quarks is then examined. The dependence of these results on φ and radii as well as on the strange quark mass is also studied.

Production of single-charm hadrons by the quark-combination mechanism in p -Pb collisions at sNN=5.02 TeV

“…Then in single-charm baryon formation the probability of the charm quark occurring two quarks with right colors can be greater than 1/9 (the stochas- [40,67,68], which can raise the yield ratio Λ + c /D 0 > 1.3 (corresponding to parameter R (c) B/M 1 in our model). In addition, the wave functions of charm hadrons will also influence the combination probability, for example, in several quark coalescence models through hadronic Wigner function [29,38,41], which suggests the significantly enhanced ratio Λ + c /D 0 0.8 in relativistic heavy-ion collisions [40] (corresponding to parameter R (c) B/M 0.7 in our model). We finally give a short summary of this subsection.…”

“…Here we treat the ratio R Some discussions on the present model in contrast with other popular (re-)combination/coalescence models applied in relativistic heavy-ion collisions [29,38,41] are necessary. In essence, our model is a statistical hadronization method based on the constituent quark degrees of freedom, in which unclear non-perturbative dynamics such as the selection of different spin states and the formation competition between baryon and meson in quark combination are treated as model parameters.…”

Enhanced production of strange baryons in high-energy nuclear collisions from a multiphase transport model

“…Such a phenomenon is also present in a recent study [44], in which a multiplicitydependent parameter is introduced in a dynamical core-corona model to describe the measured strange baryons to pion ratios in relativistic heavy-ion collisions. This is not surprising since the coalescence model used in the present AMPT model for hadronization is based on formation of hadrons from nearestneighbor quarks, instead of using the hadron Wigner functions as in more realistic approach [45,46]. Also, in ordering the sequence for partons to coalesce in the AMPT, it is currently based on the inverse of the freeze-out time, using other types of ordering could affect the values of r BM and r Y .…”

Production of light flavor and single-charmed hadrons in $pp$ collisions at $\sqrt{s}=5.02$ TeV in an equal-velocity quark combination model

“…This non-monotonic p T dependence of the ratio of baryon to meson and, in particular, the enhancement in the low p T range have been observed many times in relativistic heavy-ion collisions [48][49][50][51][52] and in pp and pPb collisions at LHC energies [8,45,53]. This typical behavior of baryon/meson ratio is usually regarded as the consequence of the quark combination mechanism at hadronization [54][55][56][57][58]. In this paper, taking Ω/φ ratio as an example, we carry out a simple derivation to further clarify the underlying physics of such p T dependence of baryon to meson ratios in the low and intermediate p T range.…”