دانلود رایگان ترجمه مقاله وابستگی ساختار منحنی درخشندگی به غلظت مواد تغلیظ در LiF (نشریه آکسفورد 1999)

وابستگی ساختار منحنی درخشندگی به غلظت مواد تغلیظ در LiF: منیزیم، مس، سدیم، سیلیس، فسفر

Dependence Of Glow Curve Structure On The Concentration Of Dopants In Lif:Mg,Cu,Na,Si Phosphor

Abstract

The dependence of dopants concentration on glow curve structure of newly developed LiF:Mg,Cu,Na,Si phosphor has been investigated. LiF samples with different dopants concentration were prepared by varying the concentrations of Mg (0– 1.0 mol%), Cu (0–1.0 mol%) and NaSi (0–2.4 mol%) and their glow curve shapes were analysed after 137Cs g irradiation. The intensity of the main peak has a strong influence on Mg concentration. The intensity of the high temperature peak tends to be reduced with increasing Cu concentration; Cu inhibits the growth of the high temperature peak. NaSi was an effective dopant to obtain the high intensity of the low temperature peak and main peak. The optimum composition of dopants was found to be Mg 0.6 mol%, Cu 0.8 mol% and NaSi 1.8 mol%. This phosphor has about two times higher sensitivity than that of LiF:Mg,Cu,P.

1 Introduction

A new TL material, LiF:Mg,Cu,Na,Si phosphor with high sensitivity and good fading characteristics was developed by Doh et al (1,2). LiF:Mg,Cu,Na,Si has a similar glow curve shape to LiF:Mg,Cu,P, but the relative TL sensitivity of LiF:Mg,Cu,Na,Si is higher by about 2 times than that of LiF:Mg,Cu,P(3). Hence it can be used for the measurement of low doses effectively, but the glow curve structure and the dosimetric characteristics are not yet well known. Doh et al (1) had selected the dopants composition of LiF:Mg,Cu,Na,Si phosphor, but this was not an optimum composition because Mg and Cu contents were determined by varying the two concentrations simultaneously.

In the present work the effects of individual dopants (Mg, Cu, NaSi) in LiF:Mg,Cu,Na,Si phosphor have been investigated by analysis of the glow curve structures and the TL intensities as a function of dopants concentration. The optimum dopants composition for this material having the maximum TL intensity has been also determined.