Thermally stimulated luminescence studies of xhyphen;irradiatedLhyphen;alanine:Cr3+have been conducted in the interval 10ndash;300 K. Glow peaks were observed at 42, 60, 72, 148, and 208 K. The 148 K peak has been previously reported, while the one at 208 K was of insufficient intensity to study. Also, the 60 K peak was difficult to analyze due to overlap with the neighboring peaks. Detailed analyses of the 42 and 72 K peaks yielded, respectively, the following parameters:E=24 meV,s=5.3 sminus;1, andl=1;E=180 meV,s=2.4times;1010sminus;1, andl=2.8, wherelis the kinetics order. Identical emission was observed from each peak, characterized by a maximum at 445 nm with FWHM equal to 0.605 eV. A tentative model is presented to explain these results in terms of detrapping and deexcitation via the excited singlet and triplet states.
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