Abstract
We present continuum extrapolated results of charmonium and bottomonium correlators in the vector channel at several temperatures below and above $T_c$. The continuum extrapolation jointly performed with the interpolations to have physical values of $J/\psi$ and $\Upsilon$ masses in the confined phase is based on calculations on several large quenched isotropic lattices using clover-improved Wilson valence fermions carrying different quark masses. The extrapolated lattice correlators are confronted with perturbation theory results incorporating resummed thermal effects around the threshold from pNRQCD and vacuum asymptotics above the threshold. An additional transport peak is modelled below the threshold allowing for an estimate of the diffusion coefficients for charm and bottom quarks. We find that charmonium correlators in the vector channel can be well reproduced by perturbative spectral functions above $T_c$ where no resonance peaks for $J/\psi$ are needed at and above 1.1 $T_c$, while for bottomonium correlators a resonance peak for $\Upsilon$ is still needed up to 1.5 $T_c$. By analyzing the transport contribution to the correlators we find that the drag coefficient of a charm quark is larger than that of a bottom quark.
Highlights
Heavy quark-antiquark bound states, quarkonia, have been proposed as a thermometer of quark gluon plasma in heavy ion collisions since they are formed at a very early stage of the collisions and may survive in the deep deconfined phase due to their hierarchically small sizes and large binding energies [1,2]
The nuclear modification factor of open flavor mesons seems to support such a picture [17,18,19]. Phenomenological explanations of these phenomena require a modeling of the heavy quark diffusion in a hot and dense medium. This requires knowledge about the heavy quark diffusion coefficients D [20,21,22,23] which can be determined in lattice QCD calculations as they are encoded in the correlation and spectral functions of quarkonia in the vector channel
From our analyses we see a qualitatively good agreement between our continuum extrapolated lattice data and the correlator obtained from perturbative spectral functions constructed from matching potential nonrelativistic QCD (pNRQCD) calculations to vacuum asymptotics
Summary
Heavy quark-antiquark bound states, quarkonia, have been proposed as a thermometer of quark gluon plasma in heavy ion collisions since they are formed at a very early stage of the collisions and may survive in the deep deconfined phase due to their hierarchically small sizes and large binding energies [1,2]. The nuclear modification factor of open flavor mesons seems to support such a picture [17,18,19] Phenomenological explanations of these phenomena require a modeling of the heavy quark diffusion in a hot and dense medium. This requires knowledge about the heavy quark diffusion coefficients D [20,21,22,23] which can be determined in lattice QCD calculations as they are encoded in the correlation and spectral functions of quarkonia in the vector channel. The results will be used to investigate the thermal modifications of J=ψ and Υ and the diffusion coefficients of charm and bottom quarks Parts of the study have been presented in various conferences and workshops [36,37,38,39,40,41,42] and in the Ph.D. thesis of Anna-Lena Lorenz [43]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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.
