  STAR collaboration has offered eminent nuclear modification factor of J/psi
at high p_T and midrapidity produced in Cu-Cu collisions at \sqrt {s_{NN}}= 200
GeV. Recalling a prediction we can understand that the feature of high-p_T
nuclear modification factor is related to c\bar c produced by 2-to-1 and 2-to-2
partonic processes in deconfined matter particularly in the prethermal stage
and to the recombination of c and \bar c. The nuclear modification factor at
high p_T is sensitive to the earliest form of deconfined matter that does not
have a temperature.
