Am242m

Am242m is a metastable nuclear isomer of the americium-242 nuclide. The designation m signals a metastable excited state of the nucleus, higher in energy than the ground state. This isotope is synthetic and is produced in nuclear facilities, typically through neutron irradiation and subsequent de-excitation of americium isotopes in reactors or accelerators.

In most cases, Am242m decays to the ground-state nucleus Am-242 by an isomeric transition, emitting gamma rays with energies characteristic of the transition. The decay mode is governed by the nuclear structure of the isomer and provides a distinct gamma-ray signature useful for spectroscopic identification and study.

Am242m generally appears only in trace amounts in samples containing americium, reflecting its metastable nature rather than a long-lived, abundant isotope. Because it is radioactive, handling and storage require appropriate radiological controls, shielding, and regulatory compliance.

Applications of Am242m are primarily in basic nuclear physics research, including investigations of nuclear structure, isomerism, and gamma spectroscopy. It is not widely used in commercial or industrial contexts, and its study is largely confined to facilities equipped to work with americium isotopes and to researchers conducting related investigations.

See also: Americium-241, Americium-242, nuclear isomer, metastable state, gamma spectroscopy.