TWO-STEP METHOD FOR SHIELDING DESIGN

                              Aurelia Laxdal
                                 TRIUMF

Abstract:
TRIUMF's ARIEL project includes two new radioactive production target stations.
The east target station will be dedicated to production from a 0.5 MW electron
beam at 50 MeV and the west target station will be driven by protons from the
500 MeV cyclotron. FLUKA shielding simulations are done for the proton target
station and the adjacent personnel occupational areas, when a 500 MeV p+ beam at
100 uA impinges onto a uranium carbide target. Since the laser port, aligned
directly with the target, extends into the mechanical service room, a maze-type
shielding is designed around the laser table, to create a personnel accessible
area into the mass separator room during beam production. In this case a
two-step method approach is suitable to optimize and finalize the shielding
configuration. In the first step hadrons are scored in an output file, with
USERDUMP, and read in as a SOURCE file in the second step. A description of the
two-step method, its filess manipulation and the required cards, will be given
in this presentation.