A particle-rotor model with a nonspheroidal axial and reflection symmetric Woods-Saxon potential has been used to describe the rotational bands and gamma branching ratios in some odd-mass nuclei with 95 to 89 neutrons. Systematics of the deformation parameters have been found by calculations in the well-deformed region. The model is capable of giving a systematic classification of the low-lying odd-parity excitations in the N = 91 and expecially in the N = 89 nuclei. An important result is the identification of the 7/2+, 3/2+ and 5/2+ members of the 3/2+[651] side band in the weakly deformed nuclei. These discoveries also provide a reliable foundation for the classification of other low-spin states.

The/?--decay of 167T~ 661Jy produced through the fast neutron reaction 17~ ~)167Dy has been investigated by using several kinds of detectors and a high-capacity two-parameter recording system. The half-life and/?--decay energy of 167Dy were determined to be T~ = 6.20 + 0.08 rain and Q~_ = 2.35 -t-0.06 MeV, respectively. The observed level scheme of 167Ht ~67 -(completely unknown previously) contains 12 states, among them a 6.0_+ 0.1 gs M2 isomer at 259.

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