Speaker
Description
Ion accelerators may produce intense secondary radiation fields from intended or unintended nuclear interactions of the accelerated particles with their environment. Besides interactions in the target or beam dump, some of the accelerated particles are unavoidably lost to the beam pipe and some other collided to scrapers and collimators resulting in intense neutron and gamma fields. These fields pose a risk for workers and public during operation, and also result in material activation, which may difficult the hands-on maintenance of the device. The proper calculation and transport of prompt and residual sources of radiation is critical for the licensing of equipment and experimental setups.
Here two new and advanced methods for radiation field calculation are presented. These methods are based on the MCNP6 code, which is one of the most used tools for radiation transport:
- srcUNED-Ac is a user-defined source module, where secondary particle
sources in typical simple geometries (pipes, scrapers, target) can
be easily defined with an arbitrary number of double differential
neutron and (prompt or residual) gamma spectra. It is a tool
intended for making quick flexible calculations for estimating
doses when accelerated particles are fully contained in the beam pipe. - MCUNEDplus is a code extension, using the detailed transport
of accelerated ions to directly compute the prompt and residual
radiation fields originated by them, or any of its progeny. Residual
gamma sources are computed using specially processed nuclear data
libraries, with the D1S algorithm, which is fully valid to most
accelerator applications.
These tools are here described with some applications to the evaluation of the IFMIF-DONES facility, based on a 125 mA, 40 MeV deuteron accelerator.