Spectral functions of charmonium with 2+1 flavours of dynamical quarks

Szabolcs Borsanyi; Stephan Dürr; Zoltán Fodor; Christian Hoelbling; Sándor D. Katz; Stefan Krieg; Simon Mages; Dániel Nógrádi; Attila Pásztor; Andreas Schäfer; Kálmán K. Szabó; Bálint C. Tóth; Norbert Trombitás

arXiv · 1410.7443

Spectral functions of charmonium with 2+1 flavours of dynamical quarks

Szabolcs Borsanyi·Stephan Dürr·Zoltán Fodor·Christian Hoelbling·Sándor D. Katz·Stefan Krieg·Simon Mages·Dániel Nógrádi·Attila Pásztor·Andreas Schäfer·Kálmán K. Szabó·Bálint C. Tóth·Norbert Trombitás

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Abstract

Finite temperature charmonium spectral functions in the pseudoscalar(PS) and vector(V) channels are studied in lattice QCD with 2+1 flavours of dynamical Wilson quarks, on fine isotropic lattices (with a lattice spacing of 0.057fm), with a non-physical pion mass of 545MeV. The highest temperature studied is approximately 1.4Tc. Up to this temperature no significant variation of the spectral function is seen in the PS channel. The V channel shows some temperature dependence, which seems to be consistent with a temperature dependent low frequency peak related to heavy quark transport, plus a temperature independent term at omega > 0. These results are in accord with previous calculations using the quenched approximation.

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Szabolcs Borsanyi, Stephan Dürr, Zoltán Fodor, Christian Hoelbling, Sándor D. Katz, Stefan Krieg, Simon Mages, Dániel Nógrádi, Attila Pásztor, Andreas Schäfer, Kálmán K. Szabó, Bálint C. Tóth, Norbert Trombitás. 2014-10-27. Spectral functions of charmonium with 2+1 flavours of dynamical quarks. https://arxiv.org/abs/1410.7443

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