The radiations of ${\mathrm{Cs}}^{134}$ (2.3 yr) and ${\mathrm{Cs}}^{134m}$ (3.15 hr) have been studied in a high-resolution beta-ray spectrometer. The gamma rays of ${\mathrm{Cs}}^{134}$ were observed both by internal and external conversion, and coincidence rates were measured between the beta continuum and the internal conversion electrons of the stronger gamma rays. The beta spectrum of ${\mathrm{Cs}}^{134}$ appears to consist of four, or possibly five, components. Nine gamma rays were found both by internal and external conversion; a tenth gamma ray appears only in internal conversion. A decay scheme is proposed which is reasonably consistent with the multipole order of each of the radiations as obtained from internal conversion data.

A search was made for a ground- or intermediate-state beta transition from ${\mathrm{Cs}}^{134m}$. No transition to the ground state was observed, but some indication was found for a weak transition to an excited state.

• Received 26 July 1954

DOI:https://doi.org/10.1103/PhysRev.97.451