| Autor: |
Mainak Roy, K.P. Muthe, B.C. Bhatt, S.K. Gupta, D.R. Mishra, S. Kannan, C. Thinaharan, M.S. Kulkarni, S.K. Kulshreshtha, D.N. Sharma |
| Rok vydání: |
2007 |
| Předmět: |
|
| Zdroj: |
Radiation Measurements. 42:170-176 |
| ISSN: |
1350-4487 |
| DOI: |
10.1016/j.radmeas.2006.06.007 |
| Popis: |
Anion defective α - Al 2 O 3 :C crystals having an intense low temperature TL peak were developed using a post-growth thermal impurification (PGTI) technique. The developed samples were studied using optical absorption (OA), thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques. The samples show two clear TL glow peaks at 64 and 175 ∘ C for a 4 K/s heating rate. It was found that abrupt cooling of the crystal from 1475 ∘ C preferentially stimulates creation of shallow traps. The low temperature ( 64 ∘ C ) TL glow peak contains almost 99% of the total integrated TL signal. The sensitivity of the developed samples was found to be about 200 times the TL sensitivity of glow peak 5 of TLD-100 with rapid fading in less than 5 min at room temperature. The high TL sensitivity of the 64 ∘ C TL peak in the developed sample may be attributed to greater availability of electron traps and luminescence recombination centers ( F + centers). Along with the intense low temperature ( 64 ∘ C ) TL peak, a relatively high ratio of F 203 nm / F 225 nm + OA band intensity was observed in the samples made by the PGTI technique, when compared with the corresponding OA band intensity ratio in commercially available α - Al 2 O 3 :C crystals. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect