A NEW HIGH ENERGY UNILAC AS AN HIGH CURRENT HEAVY ION INJECTOR FOR THE FAIR-SYNCHROTRONS

The GSI UNILAC serving as a high duty factor heavy ion linac is in operation since nearly 35 years. An upgrade program dedicated to FAIR will be finished until 2011. For the FAIR project the synchrotron SIS 18 has to be filled up to the space charge limit. After recommissioning of the UNILAC the replacement of the main DTL is foreseen. A new 4 MV/m 108 MHz IHLINAC provides a high intensity 5 MeV/u U-beam. The existing gas stripper section is reused to perform a beam intensity of 24 emA in charge state 42+. The existing UNILAC-tunnel may house a high efficient linac structure. A superconducting or normal conducting 324 MHz-CH-linac (crossbar H-structure) is under consideration as well as rf-resonators of half wave or quarter wave type. The new high energy linac should be able to boost the beam energy up to 30 MeV/u. A further upgrade option is a second 100 m-linac (324 MHz) to enhance the beam energy to up to 150 MeV/u (U), sufficient to feed the FAIR 100 Tm synchrotron in direct line. The paper will report on the ongoing conceptual layout of a new UNILAC-concept.