${\Lambda }_c$ Enhancement from Strongly Coupled Quark-Gluon Plasma

We propose the enhancement of ${\Lambda }_c$ as a novel quark-gluon plasma signal in heavy ion collisions at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider. Assuming a stable bound diquark state in the strongly coupled quark-gluon plasma near the critical temperature, we argue that the direct two-body collision between a $c$ quark and a $[ud]$ diquark would lead to an enhanced ${\Lambda }_c$ production in comparison with the normal three-body collision among independent $c$, $u$, and $d$ quarks. In the coalescence model, we find that the ${\Lambda }_c/D$ yield ratio is enhanced substantially due to the diquark correlation.

Figure 1

The yield ratios ${\Lambda }_c/D^0$ as functions of temperature.