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arXiv · 1401.5940

Charmonium spectral functions from 2+1 flavour lattice QCD

Szabolcs Borsanyi·Stephan Durr·Zoltan Fodor·Christian Hoelbling·Sandor D. Katz·Stefan Krieg·Simon Mages·Daniel Nogradi·Attila Pasztor·Andreas Schafer·Kalman K. Szabo·Balint C. Toth·Norbert Trombitas
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Abstract

Finite temperature charmonium spectral functions in the pseudoscalar and vector channels are studied in lattice QCD with 2+1 flavours of dynamical Wilson quarks, on fine isotropic lattices (with a lattice spacing of 0.057 fm), with a non-physical pion mass of $m_π \approx$ 545 MeV. The highest temperature studied is approximately $1.4 T_c$. Up to this temperature no significant variation of the spectral function is seen in the pseudoscalar channel. The vector 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 ω>0. These results are in accord with previous calculations using the quenched approximation.

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Szabolcs Borsanyi, Stephan Durr, Zoltan Fodor, Christian Hoelbling, Sandor D. Katz, Stefan Krieg, Simon Mages, Daniel Nogradi, Attila Pasztor, Andreas Schafer, Kalman K. Szabo, Balint C. Toth, Norbert Trombitas. 2014-07-02. Charmonium spectral functions from 2+1 flavour lattice QCD. https://doi.org/10.1007/jhep04(2014)132

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