The IsomerRb84m

Abstract

With the help of scintillation counters information on the isomer ${\mathrm{Rb}}^{84m}$ has been obtained. The isomer was produced by an ($n, 2n$) bombardment of ordinary Rb salts. The half-life has been determined as 21 min. Three gamma-rays have been observed at 0.239, 0.463, and 0.890 Mev. The last gamma-ray occurs in the product ${\mathrm{Kr}}^{84}$. Coincidence measurements show coincidences between the gamma-ray at 0.239 Mev and another of nearly the same energy, while coincidences between the 0.463 and the gamma-rays at 0.239 Mev are essentially negligible. A possible level scheme is discussed.