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A detailed TL investigation on MgO:Li,Tb,Sm phosphor has been carried out by studying several TL characteristics - TL glow curve structure, dose response, linearity dose behaviour, fading and reproducibility. TL glow curve structure of the phosphor reveals the presence of two TL glow peaks. The main TL glow peak of high intensity is observed at high temperature side i.e. at 162 °C and another peak of low intensity is observed at 316 °C. Further, the effect of dose on TL response of the phosphor has been studied and a new behaviour is noticed. With increasing doses, the position of main TL glow peak is similar while the second TL glow peak vanishes at higher doses. A linear TL response is observed from 10 Gy–700 Gy and becomes sublinear above 700 Gy. Low TL fading characteristics and good reproducibility have also been observed. Encouraging results suggest the applicability of doped MgO phosphor for the detection of gamma rays. • MgO:Li,Tb,Sm phosphor is synthesized using combustion method. • TL dose response is studied in the dose range 10 Gy–2000 Gy. • Single TL glow peak is present at higher doses (>200 Gy). • Linear TL dose region is observed in the dose range 10 Gy–700 Gy. • Interesting TL results are favorable for high dose gamma dosimetry. [ABSTRACT FROM AUTHOR]

• TL properties of perovskite NaMgF 3 :Tb synthesized using solid state reaction method and melting method have been investigated. • TL properties of NaMgF 3 :Tb irradiated with gamma rays is reported firstly. • Single TL glow curve structure, linear TL response for 10 Gy – 500 Gy, low TL fading characteristics has been observed for the sample prepared using melting method. • NaMgF 3 :Tb synthesized using melting method is a potential TL dosimeter for the detection of gamma rays. NaMgF 3 is a recognized sensitive thermoluminescence (TL) dosimeter but it shows fading at room temperature which limits its use as a radiation dosimeter. It is important to improve this parameter of NaMgF 3 for its potential application in the field of radiation dosimetry. Thus, the current work focuses on enhancing the dosimetric properties of NaMgF 3 exclusively the TL fading characteristics. In the present study, Tb doped NaMgF 3 has been synthesized by two different methods i.e. solid state reaction method (SSR) and melting method (MT). A comparative and detailed TL studies have been carried out after irradiation with gamma rays which has not been reported so far. Detailed analysis of TL and Photoluminescence (PL) properties reveal that NaMgF 3 :Tb prepared via MT shows good luminescence properties in comparison to SSR and previously reported results. Thus, Tb doped NaMgF 3 synthesized by melting method can be a potential dosimeter for the detection of gamma rays. [ABSTRACT FROM AUTHOR]

In the present work, the thermoluminescence (TL) properties of Yb doped CaSiO 3 phosphor exposed to gamma rays and carbon (C) ion beam have been reported. The phosphor has been synthesized using solid-state reaction method. The formation and surface morphology of the phosphor have been studied using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) respectively. The optical band gap of the phosphor is determined using UV–Visible spectroscopy. TL properties on Yb doped CaSiO 3 phosphor irradiated with carbon ion beam has been reported first time. Different TL properties like TL glow curve, dose response, fading etc. have been investigated in detail. The TL glow curve of CaSiO 3 :Yb phosphor consists of two prominent glow peaks. Under gamma irradiation, the main dosimetric peak is centered at 141 °C and other peak is centered at 265 °C. The dose response behaviour has been studied in the range 10 Gy–1000 Gy. However, C ion beam irradiated phosphor also consists similar TL glow curve structure with glow peaks shifted towards high temperature side (approx. 50 °C). The dose response behaviour of C ion beam irradiated phosphor has been examined in the ion fluence range varying from 5 × 109–5 × 1012 ions/cm2. A track interaction model is used to explain the sublinearity at higher fluences of carbon ion beam. Different ion beam parameters have been analyzed using Monte-Carlo simulation-based SRIM code. A comparative TL study of the phosphor irradiated with gamma rays and carbon ion beam suggests that gamma irradiated phosphor has shown better TL properties such as high TL sensitivity, good linear dose response (10 Gy–500 Gy), stable TL glow curve structure and low fading. Various TL trapping parameters i.e. order of kinetics, activation energy and frequency factor have been calculated using Chen's peak shape method to analyze the nature of TL traps responsible for showing different behaviour of the phosphor towards both the radiations. Good TL properties of CaSiO 3 :Yb phosphor supports its possible use in gamma dosimetry. • A phosphor CaSiO 3 :Yb is developed using solid state reaction method. • A comparative TL studies of CaSiO 3 :Yb phosphor under gamma and carbon ion beam irradiation is carried out in detail. • Effect of carbon ion beam on Yb doped CaSiO 3 phosphor is reported for the first time. • Stable TL glow peaks have been observed under both the irradiations. • Encouraging TL results of CaSiO 3 :Yb phosphor makes it a promising TL detector for gamma radiations. [ABSTRACT FROM AUTHOR]