Topological susceptibility of $N_f=2+1$ QCD from staggered fermions spectral projectors at high temperatures

Understand

We compute the topological susceptibility of $N_f=2+1$ QCD with physical quark masses in the high-temperature phase, using numerical simulations of the theory discretized on a space-time lattice.

• More precisely we estimate the topological susceptibility for five temperatures in the range from $\sim200$ MeV up to $\sim600$ MeV, adopting the spectral projectors definition of the topological charge based on the staggered Dirac operator.
• This strategy turns out to be effective in reducing the large lattice artifacts which affect the standard gluonic definition, making it possible to perform a reliable continuum extrapolation.
• Our results for the susceptibility in the explored temperature range are found to be partially in tension with previous determinations in the literature.