Thermodynamic characterizations of exotic and missing states

Abstract

Thermal shifts and fluctuations at finite temperature below the deconfinement crossover of QCD from hadronic matter to the Quark-Gluon Plasma provide a viable way to look for exotic and missing states with given quantum numbers in the hadronic spectrum. We study a realization of the Hadron Resonance Gas model in the light quark ($uds$) flavor sector of QCD to study: i) the entropy shifts, and ii) the fluctuations of electric charge, baryon number and strangeness; and extract from them the possible existence of missing and exotic states from a comparison with lattice data. The analysis of the entropy shift based on the free energy of the Polyakov loop suggests the existence of exotic hybrids $gq\bar{q}$ and $gqqq$.

Comments: 3 pages, 2 figures. Presented by E.Megias at the XVII International Conference on Hadron Spectroscopy and Structure (Hadron 2017), 25-29 September 2017, Salamanca, Spain