Europium-152 (Eu-152) is a radioactive isotope of europium with a half-life of approximately 13.5 years. It decays primarily by beta emission and also emits gamma radiation, producing a range of characteristic gamma-ray lines that make it highly detectable through gamma spectrometry. Eu-152 is typically produced artificially in nuclear reactors through neutron activation of europium-151 or in particle accelerators.

Eu-152 is primarily used as a calibration source for gamma-ray detection instruments. Its wide range of gamma emissions at well-defined energies makes it ideal for calibrating and testing gamma spectrometers used in environmental monitoring, radiological safety, and nuclear research. Eu-152 is also employed in scientific studies to investigate the behavior of europium in nuclear and chemical processes.

Eu-152 does not occur naturally in significant quantities. It is produced in controlled environments, such as nuclear reactors or laboratories, through the neutron activation of stable europium isotopes. Eu-152 can also be found in spent nuclear fuel and is a byproduct of nuclear fission. Trace amounts may be encountered in contaminated areas following nuclear activities. Its production and handling are strictly regulated to minimize environmental and health risks.