Achromatic beam transport for high current injector

The high energy beam transport section (HEBT) of High Current Injector (HCI) is ≈ 50 meters long and has many 90 deg. bends in beam halls (BH) from BH3 to BH1. It transports the beam from 97 MHz room temperature drift tube linac (DTL) in BH3 to the 97 MHz superconducting linear accelerator (SC-LINAC) in BH1. The 1.8 MeV/u ion beam at the exit of DTL is designed to have energy spread within 0.5%. Thus the beam has be transported through an achromatic bend in order to prevent the transverse emittance growth besides preserving, the time width of the beam bunch. From various achromatic configurations, the final configuration is chosen in terms of identical component selection, ease of beam tuning, placement of maximum beam diagnostics and with proper radiation safety protocols. A comparison of two beam optics configurations out of various possibilities is presented using GICOSY and TRACE 3D codes. (author)