Speaker
Description
As the increase of beam power of hadron accelerators, the damage to target material is essential. For estimation of damage such as target material used at the facility, displacement per atom (DPA), calculated by the particle flux multiplied displacement cross section, is widely employed as an index of the damage. Although the DPA is employed as the damage index of the materials, the experimental data of displacement cross-section are scarce for a proton in the energy region above 20 MeV. A recent study reports that the displacement cross section of tungsten has 8 times difference among the calculation models. Therefore, experimental data of the DPA cross-section is crucial.
The DPA cross-section can be obtained by observing the change of resistivity of the sample cooled by GM cooler to sustain the damage. The sample is placed in the vacuum chamber placed at upstream of the beam dump for 3-GeV and 30-GeV synchrotrons in J-PARC for the proton energy range between 0.4 and 30 GeV. Already, we obtained budget to carry out the same experiment for 120-GeV protons at FNAL. In order to expand the proton energy region up to 450 GeV, we are planning to perform the experiment at the HiRaDMat.