| Texto completo | |
| Autor(es): |
Cano, Nilo F.
[1]
;
Rao, T. K. Gundu
[2]
;
Silva-Carrera, Betzabel N.
[2]
;
Cruz, Sofia P. S.
[2]
;
Javier-Ccallata, Henry S.
[3]
;
Bedoya-Barriga, Yaan A.
[4]
;
Ayala-Arenas, Jorge S.
[5]
;
Watanabe, Shigueo
[2]
Número total de Autores: 8
|
| Afiliação do(s) autor(es): | [1] Univ Fed Sao Paulo, Inst Mar, Rua Doutor Carvalho de Mendonca 144, BR-11070100 Santos, SP - Brazil
[2] Univ Sao Paulo, Inst Fis, Rua Matao, Travessa R 187, BR-05508090 Sao Paulo, SP - Brazil
[3] Univ Tecnol Peru, Fac Ciencias & Ingn, Av Tacna & Arica 160, Arequipa - Peru
[4] Univ Nacl San Agustin Arequipa UNSA, Fac Ciencias Nat & Formales, Escuela Profes Matemat, Av Independencia S-N, Arequipa - Peru
[5] Univ Nacl San Agustin Arequipa UNSA, Fac Ciencias Nat & Formales, Escuela Profes Fis, Av Independencia S-N, Arequipa - Peru
Número total de Afiliações: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Luminescence; v. 221, MAY 2020. |
| Citações Web of Science: | 0 |
| Resumo | |
The mineral anhydride after gamma irradiation displays four thermoluminescence (TL) peaks at 150, 200, 268 and 338 degrees C. The kinetic parameters, namely activation energy, frequency factor and kinetic order associated with the main TL peaks have been determined using initial rise and glow curve deconvolution (GCD) methods. Defect centers induced in the mineral by gamma irradiation are studied by electron spin resonance (ESR) with a view to identify the centers responsible for the TL process. ESR spectrum at room temperature is observed to be a superposition of at least six defect centers. Center I with principal g-values g parallel to = 2.011 and g perpendicular to = 2.012 is identified as (SO4)(-) radical and the center relates to the TL peak at 200 degrees C. Centers II, III and IV are characterized by axial gtensors and all these three centers are assigned to (SO4 )(-) radicals. These centers correlate with the 268 degrees C TL peak. Center V with an isotropic g-value equal to 1.9953 is attributed to (SO3) radical and the radical is also associated with the 268 degrees C TL peak. Center VI having an isotropic g factor 2.015 is assigned to an intrinsic O- type center and the center correlates with the TL peak at 268 degrees C. Center VII displays a rhombic g-tensor and is ascribed to (SO3)(-) radical. (AU) | |
| Processo FAPESP: | 14/03085-0 - Geocronologia do quaternário da costa Sudeste e Sul do Brasil |
| Beneficiário: | Shigueo Watanabe |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |