Design of a si-pin based gamma detector used for the assessment of environmental radioactivity

Abstract

Radiation, that individuals frequently experience in daily life, is classified into two types: ionizing and non-ionizing radiation. Non-ionizing radiation is a type of radiation that we are exposed to in daily life, such as radio waves (RF). This type of radiation that does not harm the cell structure. On the contrary, ionizing radiation is a type of radiation that we are less likely to encounter in daily life, and it can cause destruction to our cells. One of the most common examples of these types of radiation is X-rays. Radiation can be exposed in two ways, internally or externally. The human body can be exposed to harmful ionizing radiation, such as inhaling dust or smoke containing radioactive materials, consuming liquids and food contaminated with radioactivity, as well as radon gas and medical sources used for treatment and diagnostic purposes. X-rays with energies ranging from 20keV to 300 keV are used in X-ray devices in hospitals. While the patient is exposed to X-rays, the technician moves to a room where he can protect himself from the radiation exposure. Since radiation workers are trained for possible dangers of the radiation exposure and the radiation protection methods. Radiation workers can keep the external radiation dose they are exposed under control with the help of their personal dosimeters in the institutions they work for. Given the fact that not everyone, like radiation workers, will be able to carry a personal dosimeter, the importance of constantly monitoring the level of spatial and environmental radiation is obvious. Nuclear power plants, research reactors, accelerators, isotope production, irradiation and sterilization facilities are places that must always be kept under control for safety. Examples in history have shown that radiation leaks can occur as a result of errors in these plants, releasing unacceptable amounts of radioactivity into the environment. In the face of such a situation, it is necessary to constantly monitor the level of ionizing radiation in certain areas in order to make the fastest intervention. In this study, a gamma detector that can monitor both spatial and environmental radiation was designed and prototype production of this system was carried out. During the construction of this detector, its simplicity, low power consumption, ability to be built with readily available materials, ability to detect radiation with as low energies as possible, which is one of the requirements in the measurement of environmental radiation, and ability to operate in rural areas as self-sufficient in terms of power were highlighted. The device basically consists of a transmitting station where all the measurements are performed in the field and transmitted to the base-station and a receiver unit where the data is received and stored by the receiving station. The sender unit consists of ten main elements. These are microprocessor (ATmega328P), solar panels, step up and down converters, power filtering circuitry, batteries, real time clock (RTC), atmospheric sensor, LoRa and a gamma detector.