Finite temperature 0−+ glueball spectrum from non-susy D3 brane of Type IIB string theory

Abstract

Here, we calculate the pseudo-scalar glueball mass at finite temperature from the holographic QCD in 3+1 dimensions. The decoupled geometry of the non-supersymmetric (non-susy) D3 brane at finite temperature, which is the solution of type IIB supergravity, is considered as the dual theory of QCD. We calculate the mass spectrum from the axion fluctuation in this gravity background using WKB approximations. Approximating the WKB equation for various orders of mass, we derive the analytical expressions of the mass spectrum of 0−+ at finite temperature. Finally, we evaluate the masses of the ground state and the first excited state of the pseudo-scalar glueball numerically, as, m−+=2.5 GeV and m−+⁎=3.8 GeV respectively, from the complete WKB equation. The mass of a given state is found to decrease with increasing temperature and becomes zero at confinement-deconfinement transition temperature which is consistent with the idea of confinement and also matches with some recent lattice results. From this temperature variation, the QCD transition point is found to be about 186 MeV.

Keywords

• Non-susy brane
• String/QCD duality
• Finite temperature glueball mass
• Pseudo-scalar glueball
• QCD phase transition