Design optimization of 100 MeV injector Linac for Indian spallation neutron source

A 100 MeV H- linac will be built as the injector for the rapid cycling synchrotron of the proposed Indian Spallation Neutron Source (SNS) at CAT. This linac will have 4.5 MeV RFQ as injector. We have studied various options for the 4.5 to 100 Me V part of the linac. This will consist of either a 20 MeV DTL (Drift Tube Linac) followed by 100 MeV SDTL (Separated Function Drift Tube Linac) or a complete SDTL up to 100 MeV. In this paper, we present the results of our physics design studies of the SDTL and DTL-SDTL configurations. The design of the matching sections between the RFQ -SDTL and RFQ -DTL- SDTL is discussed. The choice of the accelerator configuration and that of various parameters of the individual accelerator structures under consideration are discussed. (author)