The response of thermally stimulated luminescence in CVD diamonds to heavy charged particles

The thermoluminescence response of a batch of 45 commercial synthetic diamonds made by chemical vapor deposition (CVD) technique and standard thermoluminescence dosimeters (TLDs) known as MTS-N to high- and low-energy heavy charged particles (HCP) has been studied. The samples were irradiated with 12C (88 MeV/u) ions from the SIS (Schwer-Ionen synchrotron) as well as with 12C (9.7 MeV/u), 40Ar (7.1 MeV/u), 54Cr (6.1 MeV/u) and 208Pb (3.65 MeV/u) ions from the UNILAC (universal linear accelerator) at the GSI/Darmstadt, Germany. The linear energy transfer (LET) of the accelerated ions in water and the resulting dose imparted to the TLD chips were calculated to be up to 10MeV/μm for 208Pb ions. The thermoluminescence efficiency of the diamond and LiF MTS-N dosimeters relative to 60Co gammy rays was determined. The results show a decrease of the thermoluminescence (TL) efficiency with increasing LET of the absorbed radiation. However, the TL efficiency for diamond material has been found to be 45 times higher than that for LiF dosimeters in the case of irradiation with 208Pb ions.