With the kinetic freeze-out nucleons and antinucleons obtained from the quark combination model, we study the production of light nuclei and antinuclei in the (anti-)nucleon coalescence mechanism in relativistic heavy ion collisions. We derive analytic formulas of the momentum distributions of different light nuclei and apply them to compute transverse momentum $\left(p_T\right)$ spectra of (anti-)deuterons $(d$, $\overline{d})$ and (anti-)tritons $(t,$ $\overline{t})$ in Au-Au collisions at $\sqrt{s_{\mathrm{NN}}}=7.7, 11.5, 19.6, 27, 39, 54.4 \mathrm{GeV}$. We find that the experimental data available for these $p_T$ spectra can be well reproduced. We further study the yields and yield ratios of different light (anti-)nuclei and naturally explain their interesting behaviors as a function of the collision energy. We especially point out that the multiparticle yield ratio $tp/d^2$ should be carefully corrected from hyperon weak decays for protons to probe the production characteristics of light nuclei. All of our results show that the coalescence mechanism for (anti-)nucleons plays a dominant role for the production of light nuclei and antinuclei at the BNL Relativistic Heavy Ion Collider beam energy scan energies.

We improve a nucleon coalescence model to include the coordinate-momentum correlation in nucleon joint distributions, and apply it to Pb-Pb collisions at $\sqrt{s_{NN}}=2.76\mathrm{TeV}$ to study production properties of deuterons ($d$), helions (${}^3\mathrm{He}$), and tritons ($t$). We give formulas of the coalescence factors $B_2$ and $B_3$, and naturally explain their behaviors as functions of the collision centrality and the transverse momentum per nucleon $p_T/A$. We reproduce the transverse momentum spectra, averaged transverse momenta, and yield rapidity densities of $d, {}^3\mathrm{He}$, and $t$, and find the system effective radius obtained in the coalescence production of light nuclei behaves similarly to Hanbury Brown–Twiss interferometry radius. We particularly give expressions of yield ratios $d/p, {}^3\mathrm{He}/d, t/p, {}^3\mathrm{He}/p, d/p^2, {}^3\mathrm{He}/p^3, t/{}^3\mathrm{He}$ and argue their nontrivial behaviors can be used to distinguish production mechanisms of light nuclei.

Using a quark combination model with the equal-velocity combination approximation, we study the production of hadrons with strangeness and charm flavor quantum numbers in Pb+Pb collisions at $\sqrt{s_{NN}}=$ 5.02 TeV. We present analytical expressions and numerical results for these hadrons’ transverse momentum spectra and yield ratios. Our numerical results agree well with the experimental data available. The features of strange and charm hadron production in the quark–gluon plasma at the early stage of heavy ion collisions are also discussed.