Abstract
We investigate gluon correlation functions and spectral functions at finite temperature in Landau gauge on lattice QCD ensembles with N_f=2+1+1 dynamical twisted-mass quarks flavors, generated by the tmfT collaboration. They cover a temperature range from 0.8le T/T_Cle 4 using the fixed-scale approach. Our study of spectral properties is based on a novel Bayesian approach for the extraction of non-positive-definite spectral functions. For each binned spatial momentum we take into account the gluon correlation functions at all available discrete imaginary frequencies. Clear indications for the existence of a well defined quasi-particle peak are obtained. Due to a relatively small number of imaginary frequencies available, we focus on the momentum and temperature dependence of the position of this spectral feature. The corresponding dispersion relation reveals different in-medium masses for longitudinal and transversal gluons at high temperatures, qualitatively consistent with weak coupling expectations.
Highlights
Transport and thermal properties of strongly interacting matter have been extracted from the correlation functions of mesons, i.e. hadronic observables
We investigate gluon correlation functions and spectral functions at finite temperature in Landau gauge on lattice QCD ensembles with N f = 2 + 1 + 1 dynamical twisted-mass quarks flavors, generated by the tmfT collaboration
We have presented the first computation of finite-temperature gluon correlation and spectral functions in Landau gauge on full QCD ensembles with N f = 2 + 1 + 1 flavors of dynamical quarks, generated by the tmfT collaboration and gauge fixed using the cuLGT library on GPU’s
Summary
Transport and thermal properties of strongly interacting matter have been extracted from the correlation functions of mesons, i.e. hadronic observables. From a practical point of view, we are interested in using lattice gluon spectral functions to validate phenomenological models used in the description of heavy-ion collisions Some of these rely on a quasi-particle picture for the fundamental constituents of strongly interacting matter, which at high temperature is matched to resummed perturbative predictions from hard-thermal loops. In that case the gauge independent spectral feature encoding the potential is embedded in a gauge dependent background, which may be cleanly separated In this first study of gluon properties in thermal lattice QCD with N f = 2 + 1 + 1 dynamical twisted-mass flavors, we use the conventional choice of Landau gauge ∂μ Aaμ = 0, which is manifestly Lorentz invariant and retains global SU (Nc) gauge symmetry. Inverting Eq (9) using the simulated lattice correlator data, in order to obtain the spectral functions, represents a well known ill-posed problem, which we will attack via the use of Bayesian inference as laid out in detail
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
