Mechanical integration of an RF volume source and einzel lens LEBT to the SSC RFQ

The Superconducting Super Collider (SSC) LINAC Injector is currently operating with an RF-driven volume ion source coupled with an einzel lens low energy beam transport (LEBT). The ion source, LEBT and beam diagnostics are integrated into a compact vacuum enclosure which is mounted to the upstream endwall of the Radio Frequency Quadrupole (RFQ). Beam dynamic requirements imposed a minimum longitudinal space of only 23.5 cm, thus creating a very challenging packaging problem. In addition, optimum beam matching to the RFQ specified a maximum gap of 1 cm between the LEBT and the entrance endwall face, thereby excluding the use of a bellows between the LEBT chamber and the RFQ. Vacuum system induced loads and vibrations are isolated from the beamline components by the use of a straddling support frame which is an integral component of the vacuum system/support cart. This paper will describe some of the unique aspects of the mechanical design resulting from beam requirements, high gas load, availability of the vacuum system and the need for unconstrained attachment to the RFQ. In addition, the mobile installation cart and the fully automated vacuum control system will be discussed.<
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