Artigo de peri??dico
Influence of the photoionization cross-section on the OSL signal of LiF
Registro en:
0925-3467
102
10.1016/j.optmat.2020.109792
0000-0002-7362-2455
56.69
69.14
Autor
NOVAIS, BRUNA
FERRAZ, EDWARD
SOUZA, ADELMO S.
ANTONIO, PATRICIA L.
CALDAS, LINDA V.E.
BATISTA, JO??O
LIMA, HEVESON
Resumen
The understanding of the electron trapping and recombination processes is the key to successful applications
of materials in ionizing radiation dosimetry, which unfortunately are not well known yet. In this work, the
influence of the photoionization cross-section (????) was investigated on the optically stimulated luminescence
(OSL) response of the lithium fluoride (LiF) compound. The ???? has been predicted through the expression
proposed by Lima???Batista???Couto. In addition, OSL measurements were performed using the continuous-wave
stimulation mode (CW-OSL), with 60 s of light stimulation. The samples were submitted to 10 Gy and 15 Gy
of absorbed dose. Phonon dispersion and density calculations are presented by using the Density Functional
Perturbation Theory. The results, obtained by a combination of different methodologies, show that the low
sensitivity of LiF to the light stimulus (???? = 470 nm) is due to the very low magnitude of ???? at the used excitation
wavelength. A comparison with Al2O3:C was also carried out, showing that the intensity and the pattern of the
OSL curve decay are modified by the ????. These results play an important role in understanding the luminescent
properties of this material, and they open a new opportunity to improve the light sensitivity of this detector. Conselho Nacional de Desenvolvimento Cient??fico e Tecnol??gico (CNPq) CNPq: 301335/2016-8; 150117/2018-3