  The Paul Scherrer Institut (PSI) operates the Meson production target
stations E and M with 590 MeV protons at currents of up to 2.4 mA. Both targets
consist of polycrystalline graphite and rotate with 1 Hz due to the high power
deposition (40 kW at 2 mA) in Target E. The graphite wheel is regularly
exchanged and disposed as radioactive waste after a maximum of 3 to 4 years in
operation, which corresponds to about 30 to 40 Ah of proton fluence. For
disposal, the nuclide inventory of the long-lived isotopes (T(1/2) > 60 d) has
to be calculated and reported to the authorities. Measurements of gamma
emitters, as well as 3H, 10Be and 14C, were carried out using different
techniques. The measured specific activities are compared to Monte Carlo
particle transport simulations performed with MCNPX2.7.0 using the
BERTINI-DRESNER-RAL (default model in MCNPX2.7.0) and INCL4.6/ABLA07 as nuclear
reaction models.
