Tank1 of the ISAC-DTL LINAC

The first phase of the ISAC radioactive ion beam facility at TRIUMF is now completed. It combines an isotope separator-on-line with a post accelerator. In the second phase a drift-tube LINAC is required to accelerate ions with a charge to mass ratio ⩾1/6 from E=0.15 MeV/u to a final energy fully variable up to 1.5 MeV/u. Due to the relatively low intensities of some of the radioactive ion species continuous (cw) operation of the accelerator is preferred. An interdigital H type RF structure is chosen because of its very high shunt impedance. The ISAC-DTL is composed of five IH tanks and three rebunchers, operating at 105 MHz. The basic design of the structure is similar to other IH structures with the exception that the stems are water-cooled. The features of this mechanical design will be discussed and the first results of the RF tests are presented