Radiation induced radical in barium sulphate for ESR dosimetry: a preliminary study

✍ Scribed by M.A. Sharaf; Gamal M. Hassan

• Book ID: 103858700
• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 346 KB
• Volume: 225
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2004.05.025

✦ Synopsis

Barium sulphate (BaSO 4 ) was irradiated by c-rays and analyzed with electron spin resonance (ESR) to study radiation induced radicals for materials as radiation dosimeter. The ESR spectrum for the radical species is characterized by a hole-type center with g factor of 2.019, 2.0127 and 2.0103 and electron-type center with g factor of 2.0039, 2.0025 and 2.0001. The dosimetric signal with splitting factors of g ¼ 2:0039 is ascribed to SO À 3 radicals and 5G linewidth. The response to c-ray dose ranging from 5 to 10 3 Gy, energy dependence calculation and the thermal stability have been studied. The number of free radicals per 100 eV (G-value) was obtained to be 0.25 ± 0.06 and 0.9 ± 0.18 for BaSO 4 and alanine, respectively. The lifetime of radicals and the activation energy were estimated from Arrhenius plots to be approximately 325 ± 60 days, and 0.50 ± 0.09 eV respectively.