Comment to `The dependence of the anomalous J/psi suppression on the number of participant nucleons'

Abstract

The recently published experimental dependence of the J/psi suppression pattern in Pb+Pb collisions at the CERN SPS on the energy of zero degree calorimeter E_ZDC are analyzed. It is found that the data obtained within the `minimum bias' analysis (using `theoretical Drell-Yan') are at variance with the previously published experimental dependence of the same quantity on the transversal energy of neutral hadrons E_T. The discrepancy is related to the moderate centrality region: 100 < N_p < 200 (N_p is the number of nucleon participants). This could result from systematic experimental errors in the minimum bias sample. A possible source of the errors may be contamination of the minimum bias sample by off-target interactions. The data obtained within the standard analysis (using measured Drell-Yan multiplicity) are found to be much less sensitive to the contamination.