Europhys. Lett.
Volume 69, Number 1, January 2005
Page(s) 41 - 47
Section Nuclear physics
Published online 08 December 2004
Europhys. Lett., 69 (1), pp. 41-47 (2005)
DOI: 10.1209/epl/i2004-10319-x

On the possibility to search for $\mth{2\beta}$ decay of initially unstable ( $\mth{\alpha/\beta}$ radioactive) nuclei

V. I. Tretyak, F. A. Danevich, S. S. Nagorny and Yu. G. Zdesenko

Institute for Nuclear Research, MSP 03680 - Kiev, Ukraine

received 14 May 2004; accepted in final form 29 October 2004
published online 8 December 2004

An alternative method to search for $2\beta$ decay is discussed. Contrary to the "conventional" approach (where only $\beta$ stable $2\beta$ candidates are used), it is intended to study $\alpha/\beta$ unstable nuclei, whose $2\beta$ energy release, $Q_{\beta\beta}$, is much higher in most of the cases than that of "conventional" $2\beta$ candidates. As an example, the first experimental half-life limits on $2\beta$ decay of radioactive nuclides from $\chem{U}$ and $\chem{Th}$ families (contaminants of the $\chem{CaWO_4}$ and $\chem{CdWO_4}$ scintillators) were set by reanalyzing the data of low-background measurements in the Solotvina Underground Laboratory (1734 $\un{h}$ with $\chem{CaWO_4}$ and 13316 $\un{h}$ with $\chem{CdWO_4}$).

23.40.-s - $\beta$ decay; double $\beta$ decay; electron and muon capture.

© EDP Sciences 2005