Shielding and Activation Analyses for Beam Test Facility at SNS
The beam test facility (BTF) will be a copy of the accelerator front end of the Spallation Neutron Source (SNS) facility and will be used for test and development of new front-end equipment, for conducting research in accelerator physics (in a further build-out) for the SNS second target station moderator development (tests). The BTF is assembled and will be operating in the radio frequency (RF) on-site annex building. Negatively charged hydrogen ions (H{sup -}), generated at the ion source, will be accelerated to 2.5 MeV. The facility is capable of producing one-ms-long pulses at 60 Hz repetition rate with up to 50 mA peak current. This beam will be safely terminated in the beam stop. In order to support the BTF project from a radiation protection point of view, neutronics simulations and activation analyses were performed to develop shielding around the beam stop, evaluate dose rates in case of an accident and to evaluate the radionuclide inventory at the facility end-of-life for decommissioning. The challenge of the analyses was to consider low energy charges particles reaction physics to fit the calculations into our routine transport and activation methods as practiced for the much higher energy spallation environment. (authors)