Rotational bands in⁷⁷Kr

Collective bands in⁷⁷Kr have been studied with the help of γ singles spectra, γγ coincidences, γ ray angular distributions and recoil-distance life time experiments measured during the irradiation of⁶³Cu and⁶⁴Ni targets with¹⁶O ions. Positive and negative parity bands with the following level energies, spins, and parities have been found: g.s. 5/2⁺; 150.1 keV 7/2⁺; 279.1 9/2⁺; 784.8 11/2⁺; 1003.7 13/2⁺; 1660.5 15/2⁺; 1919.1 (17/2⁺); 66.5 keV (3/2)^-; 245.3 (5/2)^-; 499.6 (7/2)^-; 799.5 (9/2)^-; 1177.3 (11/2)^-; 1569.9 (13/2)^-; 2063.2 (15/2)^-. A mean life time of 170±17 nsec for the 66.5 keV state was measured with γγt coincidences and a mean life time of 48±13 psec for the 245.3 keV state was obtained with a recoildistance Doppler shift measurement.