We discuss how the spectral changes of quarkonia at Tc can reflect the 'critical' behaviour of QCD phase transition. Starting from the temperature dependences of the energy density and pressure from the lattice QCD calculation, we extract the temperature dependences of the scalar and spin 2-gluon condensates near Tc. We also parameterize these changes into the electric and magnetic condensates near Tc. While the magnetic condensate hardly changes across Tc, we find that the electric condensate increases abruptly above Tc. A similar abrupt change is also seen in the scalar condensate. Using the QCD second-order Stark effect and QCD sum rules, we show that these sudden changes induce equally abrupt changes in the mass and width of J/ψ, both of which are larger than 100 MeV at slightly above Tc.
|Journal||Journal of Physics G: Nuclear and Particle Physics|
|Publication status||Published - 2008 Oct 1|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics