When performing gamma spectroscopy, which detector is primarily used?

Gamma spectroscopy primarily utilizes semiconductor detectors, particularly high-purity germanium (HPGe) detectors. These detectors are favored because they offer excellent energy resolution, which is crucial for distinguishing between different gamma-ray energies emitted from radioactive sources. The superior resolution allows for the accurate identification of isotopes and their quantification based on the energy of the gamma rays detected.

Semiconductor detectors operate by using a semiconductor material that generates charge carriers (electrons and holes) when gamma photons interact with it. The energy of the gamma photons is converted into electric signals that can be analyzed to determine the energy spectrum of the radiation.

Other types of detectors, while useful in various radiation detection applications, do not provide the same level of resolution needed for gamma spectroscopy. Geiger-Muller counters, for instance, are effective for detecting and counting radiation, but they do not measure energy levels precisely. Radiochemical detectors are used for different analytical purposes, primarily involving chemical assays rather than direct energy measurements of gamma photons. Photoionization detectors are typically used for detecting volatile organic compounds and are not suited for gamma radiation detection.

Thus, the semiconductor detector is the most appropriate choice for performing gamma spectroscopy due to its ability to provide detailed energy spectra essential for radiation analysis.