Final results of the double $\beta$ decay experiment, performed with the help of low background ${}^{116}{\mathrm{CdWO}}_4$ crystal scintillators in the Solotvina Underground Laboratory, are presented. In particular, the revised half-life value of the two-neutrino 2β decay of ${}^{116}\mathrm{Cd}$ has been measured as $T_{1/2}^{2\nu }{=2.9\mathrm{}}_{-0.3}^{+0.4\mathrm{}}\times {10}^{19}\mathrm{yr},$ and the new half-life limit on the neutrinoless $2\beta$ decay of ${}^{116}\mathrm{Cd}$ has been established as $T_{1/2}^{0\nu }>~1.7\left(2.6\right)\mathrm{}\times {10}^{23}\mathrm{yr}$ at 90% (68%) C.L. The latter corresponds to a restriction on the neutrino mass: $m_{\nu }<~1.7\left(1.4\right)\mathrm{}\mathrm{eV}$ at 90% (68%) C.L. Besides, new $T_{1/2}$ bounds (at the level of ${10}^{17}–{10}^{21}\mathrm{yr})$ were set for various $2\beta$ processes in ${}^{106}\mathrm{Cd},$ ${}^{108}\mathrm{Cd},$ ${}^{114}\mathrm{Cd},$ ${}^{180}\mathrm{W},$ and ${}^{186}\mathrm{W}$ nuclei.

• Received 21 March 2003

DOI:https://doi.org/10.1103/PhysRevC.68.035501