ABSTRACT
The diagnostic designs for the Laser Megajoule (LMJ) will require components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiations, and, in some cases, debris and shrapnel, at levels several orders of magnitude higher than those experienced today on existing facilities. The lessons learned about the vulnerabilities of present diagnostic parts fielded mainly on OMEGA for many years, have been very useful guide for the design of future LMJ diagnostics. The present and future LMJ diagnostic designs including this vulnerability approach and their main mitigation techniques will be presented together with the main characteristics of the LMJ facility that provide for diagnostic protection.
ABSTRACT
A three-dimensional neutronic modelling of the LMJ facility has been performed. The Monte Carlo transport code TRIPOLI is used to obtain the neutron spectra required for the inventory code FISPACT. Nodal activation responses and time-dependent decay gamma spectra are produced and used as source terms for further treatment by TRIPOLI for a range of engineering and safety assessments. It is shown that three-dimensional neutronic and nodal activation can be performed in a convenient way and the results obtained by this procedure will serve as a data-base for design and S&E analysis.
