The phase transition in QCD with broken SU(2) flavour symmetry

TL;DR

This study examines how the QCD transition temperature varies with different u/d quark mass ratios, finding it remains constant when measured in certain units, despite mass ratio changes.

Contribution

First investigation of the QCD transition temperature for two flavors of staggered quarks with unequal masses at specific lattice spacings.

Findings

T_c remains unchanged in units of m_rho and Lambda_MSbar despite mass ratio variation.

Transition temperature is insensitive to u/d quark mass ratio within the studied range.

Results bracket the physical quark mass ratio value.

Abstract

We report the first investigation of the QCD transition temperature, T_c, for two flavours of staggered quarks with unequal masses at lattice spacings of 1/4T. On changing the u/d quark mass ratio in such a way that m(pi_0)^2/m(pi_+)^2 changes from 1 to 0.78, thus bracketing the physical value of this ratio, we find that T_c remains unchanged in units of both m_rho and Lambda_MSbar.