ISAC targets

The TRIUMF-ISAC radioactive ion beam facility was designed and constructed to allow irradiation of thick targets with up to 100  $\upmu $ A proton beam intensities. Since beginning operation in 1998, beam intensities on ISAC targets have progressively increased toward the 100  $\upmu $ A design limit. Routine operation with p^?+? intensities up to 75  $\upmu $ A is currently possible for both refractory metal target materials and for composite metal carbide materials; full 99  $\upmu $ A p^?+? intensity has been achieved for Nb foil target material. Consideration must be given to the beam power deposition, the power dissipation and the limiting temperature criteria of each target material. Increased beam power dissipation has been achieved by modifying target materials and target containers. Increasing irradiation currents have produced benefits, drawbacks and unexpected results for ISOL operations.