Present status of charmonium spectroscopy in pp annihilations

Fermilab E835 Collaboration is committed to complete the study of the charmonium spectrum by means of pp annihilations, obtained by intersecting the Fermilab Antiprotn Accumulator with an internal hydrogen jet target. In this paper we report the preliminary results from the 1996/1997 fixed target run, particularly about η c mass and width, search for η′ c and first observation of the X 0 state in pp annihilations.