Slow component suppression and γ radiation hardness of BaF_2 crystal modified by photonic band multilayer filter
On the basis of the different emission bands between the fast and slow components in BaF_2 crystal, the photonic band multilayer filter with 3.5 periods of Al_2O_3/MgF_2/Al/MgF_2... was designed and developed in order to suppress the slow component of the scintillation light in BaF_2. It is shown that the filter can increase more than 80 times of the ratio of the intensities of the fast emission to the slow one, while the transmission, emission and decay time spectra of BaF_2 crystal modified by the filter are not changed apparently after ~(60)Co γ-ray irradiation under the dose of 10~5 Gy. The results indicate that BaF_2 crystal modified by the filter can not only avoid the interference of the slow component effectively, but also keep the good radiation resistance.