Investigation of $\beta^+$EC, EC/EC processes in $^{74}$Se
Résumé
Investigation of double beta decay processes (β+EC, EC/EC) of 74Se was performed at the Modane underground laboratory (LSM, France, 4800 m w.e.) using ultra low-background HPGe detector Obelix with sensitive volume of 600 cm3 and a sample of natural selenium with a mass of 1.6 kg, containing ∼0.89% (∼14.24 g) of 74Se. New experimental limits (at 90 % CL) on double beta decay transitions of 74Se to the ground and exited states of 74Ge were obtained from the preliminary calculation of experimental data accumulated in 135 days.