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

Abstract

We apply an equal-velocity quark combination model to study the production of light-flavor hadrons and single-charmed hadrons at midrapidity in $pp$ collisions at $\sqrt{s}=5.02$ TeV. We find experimental data for $p_T$ spectra of $\Omega$ and $\varphi$ exhibit a quark number scaling property, which is a clear signal of quark combination mechanism at hadronization. Experimental data for $p_T$ spectra of $p$, $\Lambda$, $\Xi$, $\Omega$, $\varphi$ and $K^{\ast 0}$ are systematically described by the model. The non-monotonic $p_T$ dependence of $\Omega /\varphi$ ratio is naturally explained and we find it is closely related to the shape of the logarithm of strange quark $p_T$ distribution. Using $p_T$ spectra of light-flavor quarks obtained from light-flavor hadrons and a $p_T$ spectrum of charm quarks which is consistent with perturbative QCD calculations, the experimental data for differential cross-sections of $D^{0,+}$, $D_s^{+}$ and ${\Lambda }_c^{+}$ as the function of $p_T$ are systematically described. We predict the differential cross-sections of ${\Xi }_c^{0,+}$ and ${\Omega }_c^0$. The ratio ${\Xi }_c^{0,+}/D^0$ in our model is about 0.16 and ${\Omega }_c^0/D^0$ is about 0.012 due to the cascade suppression of strangeness. In addition, the predicted ${\Xi }_c^{0,+}/D^0$ and ${\Omega }_c^0/D^0$ ratios exhibit the non-monotonic dependence on $p_T$ in the low $p_T$ range.

Comments: 11 pages, 9 figures