TL emission spectra

The TL emission spectra of feldspars have been reported in the past by a number of workers (1-6). Recently, measurements of TL emission spectra of feldspars with the help of spectrometers of much increased sensitivity have been reported (7-9). TL spectra presented in this paper are recorded with the help of a new high-sensitivity spectrometer based on Fourier transform spectroscopy. 

Figure 9.12 TL emission spectra of AIN ceramics irradiated with beta radiation obtained at different heating temperatures indicated in the figure.

Gadolinium is mostly three-valent. However, in alkali halides it is known to enter in the divalent form. Sastry and Murahdharan (1988a) have studied the optical absorption, PL spectra, PSL and TL emission spectra of RbCEGd. The crystals were quenched... 

Chakrabarti et al. (1988a) concentrated on the OSL of MgS Ce,Sm and MgS Eu,Sm. From the OSL and TL emission spectra it has been concluded that the process involved in the OSL differs from that in the TL emission in OSL, Ce (or Eu) acts as the recombination center and Sm as electron trap, whereas in TL emission, Sm acts as the recombination center and Ce (or Eu) as the hole trap. 

Jassemnejad and McKeever (1987) studied the optical absorption and the TL emission spectra of RT y-irradiated CaF2 Ce. Two major TL peaks appeared at 130 and 350°C (at 2°Cs ). Based on the thermal stability of the various radiation induced absorption bands and on the TL emission spectra, the authors suggested that the 130 C TL peak is due to recombination of electrons released from Ce " ions at cubic (Oh) sites and perturbed Vk centers, resulting in 290 nm emission. The 350"C peak was assumed to involve re-absorption of part of the 290 nm emission by overlapping absorption bands related to Ce + ions at C4v sites resulting in (Ce +) excited ions. The Ce + doublet at 320, 340 nm is then emitted on the relaxation of the excited ions. 

A review of the progress in the understanding and applications of the TL of R-doped (and Mn-doped) Cap2 phosphors was given by Jain (1990). It also discusses effects of the radiation doses and of the LET on the GCs. Optical absorption ESR and TL emission spectra which lead to the identification of traps and luminescence centers are also given. 

Barkyoumb et al. (1997) studied the low-temperature TL of CaS04 Dy. The TL emission spectra taken after irradiation at 20 K showed the main bands at 490 and 580 nm related to the Dy transitions from the Fg/2 level to His/2 and Hi3/2 respectively. The spectra taken at 200 K also showed the above main bands but with a structure of weak... 

Fig. 34. TL emission spectra (at 350 K) of X-ray-irradiated YjSiOjiSiiiaoi. Tb, for different values ofy (1) -0, (2) -0.1 and (3) -0.001. The ordinate q, denotes the relative quantum output.

In order to identify the nature of photoluminescence (PL) centers, the TL emission spectra are measured. Figure 4 demonstrates the component of TL corresponding to different spectral range of... 

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