Quark-diquark string tension, excited baryonic resonances and thermal fluctuations

Abstract

We study the baryonic fluctuations from second to eighth order involving electric charge, baryon number and strangeness below the quark-gluon plasma crossover and numerically known from lattice QCD calculations. By considering a particular realization of the Hadron Resonance Gas model, we provide evidence on the dominant role of quark-diquark degrees of freedom to describe excited baryonic resonances. After proving by means of suitable Polyakov loop correlators that the quark-diquark and the quark-antiquark forces coincide, $V_{\bar{q}q}(r)=V_{\bar{q}D}(r)+\text{const}$, we find that the corresponding susceptibilities can be saturated with excited baryonic states in a quark-diquark model picture.

Comments: 17 pages, 7 figures, 1 table; v2 typos corrected, added references, introduction and Sec. 4.3 extended. arXiv admin note: text overlap with arXiv:1812.09365