Hidden-Beauty Broad Resonance $Y_b(10890)$ in Thermal QCD

Abstract

In this work, the mass and pole residue of resonance $Y_b$ is studied by using QCD sum rules approach at finite temperature. Resonance $Y_b$ is described by a diquark-antidiquark tetraquark current, and contributions to operator product expansion are calculated by including QCD condensates up to dimension six. Temperature dependences of the mass $m_{Y_b}$ and the pole residue $\lambda_{Y_b}$ are investigated. It is seen that near a critical temperature $(T_c\simeq190~\mathrm{MeV})$, the values of $m_{Y_b}$ and $\lambda_{Y_b}$ are decreased to $87\%$, and to $44\%$ of their values at vacuum.