Impact of a thermal medium on newly observed Zcs(3985) resonance and its b-partner

Abstract

Motivated by the very recent discovery of the strange hidden-charm exotic state Zcs(3985) by the BESIII Collaboration, we study the possible interpretation of this exotic state the both at T= 0 and T≠ 0. We analytically compute the mass and meson-current coupling constant of this resonance with spin-parity JP= 1 + at finite temperature approximation up to the sixth order of the thermal operator dimension including non-perturbative contributions. Extracting thermal mass and meson-current coupling constant sum rules, the modifications on properties of the Zcs(3985) state in hot medium are determined. As a by-product, the hadronic parameters of the bottom partner of Zcs(3985) is estimated as well. The search for temperature effects on the hadronic parameters of the hidden-charm meson Zcs(3985) and the bottom partner enable us to understand the phase transitions, chiral symmetry breaking, and the properties of hot-dense matter in QCD. Moreover, the full width of the resonance Zcs(3985) is calculated as (12.0±0.8)MeV using the strong decay in the tetraquark picture. Results for width and mass are in reasonable agreement with existing experimental data and results of other theoretical works. The information obtained about the parameters of the considered states is useful for experimental investigations of exotic mesons.