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Phosphors composed of Gd 1-x RE x AlO 3 (0≤x ≤ 5 RE = Dy or Pr) stoichiometries were synthesized using the reverse coprecipitation pathway. The thermoluminescent responses of all phosphors were studied under beta radiation exposure. Doping the gadolinium aluminate host improved the thermoluminescent response of the phosphors, with the phosphors composed of Gd 0.99 Dy 0.01 AlO 3 and Gd 0.95 Pr 0.05 AlO 3 being the most sensitive. The Dy 3+ ions produced a higher improvement of the thermoluminescent signal than the Pr 3+ ions. Additionally, a proportional relationship between the similarity of the atomic numbers of the dopant and replaced ions and the sensitivity to thermoluminescence was confirmed. Besides, a slight shift of the thermoluminescent peaks toward lower temperatures was detected for doped phosphors. In the repeatability tests applied to the phosphor composed of Gd 0.99 Dy 0.01 AlO 3 , an anomalous increase in sensitization was observed. The observed sensitization was associated with the formation of electron trap clusters resulting from the continuous exposure to beta radiation. Furthermore, another sensitization phenomenon was detected in the phosphor with Gd 0.95 Pr 0.05 AlO 3 stoichiometry when it was heated at low temperatures. The aforementioned striking behavior was related to quasi-continuous distributions of electron traps and the tunneling effect. In regard to linearity, the phosphor composed of Gd 0.99 Dy 0.01 AlO 3 exhibited a linear response with the dose across the entire range of beta doses. However, the response of the Gd 0.95 Pr 0.05 AlO 3 phosphor lost linearity beyond 26.4 Gy of beta dose. The results obtained through the use of the T max -T stop method and deconvolutions suggested an enhancement in the efficiency of the thermoluminescent mechanisms due to the incorporation of activators., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Juan Zarate Medina reports financial support was provided by National Council on Science and Technology (CONACYT-MEXICO)., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The suitable choice of an activator and host combination is essential for synthesizing very sensitive thermoluminescence phosphors. In addition, conspicuous synthesis variables must be optimized to achieve the maximal response. The research presented herein shows that the most recommendable conditions to improve the thermoluminescence response of beta irradiated Gd 1-x Eu x AlO 3 phosphors were: x = 0.02 for europium stoichiometry and 1500 °C for the calcination temperature. The glow curve recorded for the most sensitive phosphor was partially erased by photo-bleaching, and thus, should yield optically stimulated luminescence., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Juan Zarate Medina reports was provided by National Council for Science and Technology. Juan Zarate Medina reports equipment, drugs, or supplies was provided by National Council for Science and Technology., (Copyright © 2022 Elsevier Ltd. All rights reserved.)