Bottomonium suppression in heavy-ion collisions and the in-medium strong force

A large suppression of various bottomonium states in ultra-relativistic heavy-ion collisions has been reported by the STAR collaboration at the Relativistic Heavy-Ion Collider.This observation is consistent with the formation of a quark-gluon plasma,but similar findings in more energetic collisions at the Large Hadron Collider suggest that a consistent picture requires additional mechanisms.Bound states of a heavy quark (charm or bottom) and its antiquark,commonly referred to as quarkonia,have long been recognized as excellent probes of quark-gluon plasma(QGP) formation in high-energy collisions of atomic nuclei.In the vacuum,most quarkonium states are dominantly bound by a linearly rising potential (the so-called Cornell potential,see Fig.1),as a direct manifestation of the confinement property of Quantum Chromodynamics (QCD).