Studying Diquark Structure of Heavy Baryons in Relativistic Heavy Ion Collisions

Abstract

We propose the enhancement of ${\Lambda }_c$ yield in heavy ion collisions at RHIC and LHC as a novel signal for the existence of diquarks in the strongly coupled quark-gluon plasma produced in these collisions as well as in the ${\Lambda }_c$. Assuming that stable bound diquarks can exist in the quark-gluon plasma, we argue that the yield of ${\Lambda }_c$ would be increased by two-body collisions between $ud$ diquarks and $c$ quarks, in addition to normal three-body collisions among $u$, $d$ and $c$ quarks. A quantitative study of this effect based on the coalescence model shows that including the contribution of diquarks to ${\Lambda }_c$ production indeed leads to a substantial enhancement of the ${\Lambda }_c/D$ ratio in heavy ion collisions.

Comments: Prepared for Chiral Symmetry in Hadron and Nuclear Physics (Chiral07), Nov. 13-16, 2007, Osaka, Japan