The E835 experiment at Fermilab

摘要

The resonant formation of charmonium states in pp annihilations has beenstudied at Fermilab by the E835 experiment, which has taken data from October 1996through September 1997 and, in a second run, from January through November 2000.In this talk we will review the most significant physics results of E835 concerning themasses and widths of the charmonium states. We will present a new, high-precisionmeasurement of the ψ(2S) total width. Furthermore we will present a measurementof the proton magnetic form factor in the timelike region.