Total Absorption Spectroscopy Study of the Beta Decay of $^{86}$Br and $^{91}$Rb

Understand

The beta decays of $^{86}$Br and $^{91}$Rb have been studied using the total absorption spectroscopy technique.

• The radioactive nuclei were produced at the IGISOL facility in Jyv\"askyl\"a and further purified using the JYFLTRAP.
• $^{86}$Br and $^{91}$Rb are considered to be major contributors to the decay heat in reactors.
• In addition $^{91}$Rb was used as a normalization point in direct measurements of mean gamma energies released in the beta decay of fission products by Rudstam {\it et al.} assuming that this decay was well known from high-resolution measurements.