Beam dump simulations for ELBE

Design studies have been performed for beam dumps of the radiation source ELBE to dissipate the maximum power of 50 kW. The results are presented in the Report FZD-267 (ps-File ,6 MB) and in the Annual Report 1998/1999 of the Institute of Nuclear and Hadron Physics (1) , (2) , (3) .
Nuclear physical and thermal properties of selected materials are considered. The construction materials have to meet requirements as low specific energy deposition, heat resistance combined with sufficient thermal conductivity, modest neutron production rate and prevention of material activations. The energy deposition and neutron production were calculated for a special design of the beam dump (Fig. 1) regarding several materials for the dump core.
For those Monte-Carlo simulations the particle transport program packages GEANT, MCNP and FLUKA have been used. The GEANT program package was used to study the power dissipation by electron showers in the cylindrical graphite dump shielded by iron plates in the concrete environment of the accelerator hall (Fig. 2). The program packages MCNP and FLUKA were used to calculate neutron fluences. The expected activations of several dump materials according to the photo-neutron reaction and neutron induced secondary reactions under beam conditions were estimated using the obtained neutron fluence and experimental cross sections from the nuclear data bases EXFOR and ENDF. Purified graphite, aluminium and titanium have been favored as construction materials.

Fig. 1: Construction of the beam dump

Fig. 2: Power released in the graphite core for a 50 MeV electron beam

contact: B. Naumann, W. Neubert