Growth of ZnWO4 crystal scintillators for high sensitivity 2β experiments

Large volume zinc tungstate crystal scintillators (up to 50 mm in diameter and 100 mm length) with improved energy resolution were developed as result of advances in crystal growth. The energy resolution of one-centimeter cube ZnWO4 crystals showed energy resolution in the range 8-10% for 662 keV gamma line of Cs-137. A value of 13.7% has been obtained with a large sample emptyset 44 x 55 mm. The radioactive contamination of a ZnWO4 26. x 24 x 24 mm detector was tested in the Solotvina Underground Laboratory. The obtained results demonstrate ability to use ZnWO4 in order to search for 2 beta-decay of Zinc and Tungsten.