Cold tests of HOM absorber material for the ARIEL eLINAC at TRIUMF

At TRIUMF development of a 50 MeV electron accelerator is well under way. Five 1.3 GHz, superconducting 9-cell cavities will accelerate 10 mA electrons to a production target to produce rare isotopes. Each cavity will provide 10 MV accelerating voltage. Plans to upgrade the accelerator in the future to a small ring with ERL capabilities requires that the shunt impedance of the dipole higher order modes to be less than 10 M Ω . The design of the accelerator incorporates beam line absorbers to reduce the shunt impedance of potentially dangerous dipole modes. rformance of the absorber is dependant on its electrical conductivity at the operational temperature. Measurements of the electrical conductivity in RF fields of a sample of the proposed beam line absorber material at room temperature and at its operational temperature will be presented for frequencies between 1.3 and 2.4 GHz.