Gamma ray detectors are sophisticated devices used to measure and analyze gamma radiation, the most energetic form of electromagnetic radiation. They play a crucial role in various fields, including nuclear science, astrophysics, and medical imaging. Leading manufacturers, such as ORTEC and Canberra Industries, offer a range of detectors with varying sensitivities, efficiencies, and applications. Advanced research organizations, such as the University of California, Berkeley and the European Space Agency, are actively involved in developing novel detector technologies with improved performance and wider applications.