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Abstract Passive dosimeters enabling accurate measurement of doses from gamma rays to visible light are necessary to ensure efficient utilization of electromagnetic radiation in numerous fields like medical diagnostics and industrial manufacturing. The specific requirements for dosimeters in terms of dosimetry range, sensitivity, accuracy, and stability for each application have led to the development of various dosimeters based on new materials and new mechanisms. Here, a comprehensive review of different types of dosimeters classified according to the response signal, namely electron paramagnetic resonance, electrical, and optical, is provided. This review starts with a general introduction to dosimetry, a classification of dosimeters, and an elucidation of the necessity of dosimeters in various ranges of the electromagnetic spectrum. This is followed by an overview of the fundamental requirements of dosimeters, an explanation of the general dosimetry procedure, and the dosimetric quantities. Emphasis is given to the working mechanism, the design concept, and applications of each type of dosimeter as well as their respective strengths and drawbacks. Challenges and prospects are presented at the end of the review. This review provides an insightful overview of the material‐mechanism‐characteristics‐application relationship of different types of dosimeters that hopefully can serve as inspiration for the development of new devices. 

Proton radiography is a promising development in proton therapy, and researchers are currently exploring optimal detector materials to construct proton radiography detector arrays. High-density glass scintillators may improve integrating-mode proton radiography detectors by increasing spatial resolution and decreasing detector thickness. We evaluated several new scintillators, activated with europium or terbium, with proton response measurements and Monte Carlo simulations, characterizing relative luminosity, ionization quenching, and proton radiograph spatial resolution. We applied a correction based on Birks’s analytical model for ionization quenching. The data demonstrate increased relative luminosity with increased activation element concentration, and higher relative luminosity for samples activated with europium. An increased glass density enables more compact detector geometries and higher spatial resolution. These findings suggest that a tungsten and gadolinium oxide-based glass activated with 4% europium is an ideal scintillator for testing in a full-size proton radiography detector. 

Five bismuth-organic materials that exhibit fluorescence or phosphorescence and radioluminescence are reported, with the photophysical behavior dependent on both the identity of the outer sphere fluorophore and noncovalent interactions.