Gamma-Gamma Directional Correlations in ⁹⁹Tc

Abstract

Gamma-gamma directional correlation studies have been carried out for 740–181, 740–(41)–140, 140–41 and 740–41 keV cascades in ⁹⁹Tc observed in the radioactive decay of ⁹⁹Mo. These investigations confirm 3/2⁺ spin assignment for 921 keV level. The mixing ratios of 740, 140 and 41 keV gamma rays are found to be predominantly E2+<1%M1, 95%M1+(5±1)%E2 and predominantly M1+(0.7_−0.4^+0.5)%E2 respectively.