A reliable dosimetry is fundamental for quality assurance of the processes and irradiation products. All dosimetric systems for high doses have some limitation with regard to their use. Dosimetric system should be easy to use, fast to measure, and of low cost. Good phosphor which shows high luminescence properties may fulfil the above criteria in some way. MgAl2O4: Dy phosphor has been prepared by solution combustion technique and confirmed with the help of XRD. ML has been excited impulsively by dropping a load of mass 0.7？kg onto the phosphors from various heights; two distinct ML peaks are observed for all the samples. It is observed that MgAl2O4: Dy phosphor shows linear response to gamma-ray dose and low fading which can be used for dosimetric purpose. 1. Introduction Dosimeters have to measure accurately radiation intensities. Their applications include personnel monitoring, environmental monitoring, radiation therapy, diagnostic radiology, and other radiation measurements. Ionization chambers measure directly intensities of ionizing radiation. For many applications, such as personnel and environmental monitoring, the absorbed energy has to be stored for long periods. This is done by suitable storing element fading of luminescence. The longer a phosphor stands after the excitation, the more trapped carriers will leave the traps, and the subsequently measured luminescence peaks will be weaker. Ionizing radiation is a technique widely employed in last decades. It was used for a long time for many applications such as sterilization of medical devices. Rare earth doped phosphors have a vital role as radiation detectors in many fields of fundamental and applied research, such as clinical, personal, and environmental monitoring of ionizing radiation [1, 2]. Various methods of preparation have also been developed for easy synthesis of these materials to make them available easily. While irradiation usually leads to the creation of structural defects, the healing effect of irradiation is also known [3]. Metals made of powders preliminary irradiated by electrons or gamma irradiations are characterized by the absence of big pores and fine homogeneous grain structure. The average sizes of grains are 4-5 times lower than that in conventional technology [4]. Ionising radiation has been found to be widely applicable in modifying the structure and properties of polymers and can be used to tailor the performance of either bulk materials or surfaces. Improved luminescent characteristics of some of aluminates have also found their place in optoelectronics. The
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