Phase structure of many flavor lattice QCD at finite temperature

TL;DR

This paper develops a lattice method to identify the critical mass for phase transitions in many-flavor QCD models, aiding the study of baryogenesis scenarios in technicolor theories.

Contribution

It introduces a new lattice approach to determine the critical mass separating first order and crossover transitions for varying flavor numbers.

Findings

Critical mass increases with the number of flavors (Nf)

Method successfully applied to Nf-flavors with light two-flavors

Provides a tool for exploring phase transitions relevant to baryogenesis

Abstract

In realistic technicolor models containing many fermions, the electroweak baryogenesis offers a natural scenario for generating baryon number asymmetry. One of the key ingredients is the occurrence of the first order phase transition at finite temperature. As a first step toward the exploration of this possibility on the lattice, we develop an agile method to identify the critical mass for a given Nf, separating the first order and the crossover transition. We explain the outline of our method and demonstrate it by determining the critical mass of Nf-flavors in the presence of light two-flavors. It is found that the critical mass becomes larger with Nf.