Radiation detection and measurement

Nuclear radiation detectors are required in all the major fields of nuclear science and technology. Radiations which are detected are (a) alpha, (b) beta, (c) gamma and (d) neutron. Radiation cannot be detected by human senses. A variety of hand held and laboratory instruments is available for detecting and measuring radiation. The most common hand held or portable instruments are: Gas ionization detectors (Ionization chambers, Proportional counters, Geiger-Mueller counters with Geiger-Mueller (GM) Tube or Probe), Scintillation detectors (Micro R Meter with Sodium Iodide Detector), Neutron REM Meter with Proportional Counter, Semiconductor detectors Chemical detectors, Film based imaging detectors used for detection of neutrons (Cr-39) and Radon Detectors (LR-115). In view of these hand held radiation detectors, it is mentioned that detection of nuclear radiation falls into two principal categories, single element detectors and imaging detectors. The working principle of detectors used to detect all these four types of radiation will be explored in detail. Uncertainty in the measurement of activity of a radioactive sample emitting alpha, beta, gamma or neutron via its detection using the suitable detector will be presented. Importance of image analysis for film based neutron and radon detection will be explored. (author)