Nuclear structure of ¹⁵⁸ Dy from interacting boson model-1

The rotational and vibrational characteristics of the g-, β-, γ- and other higher bands of even Z and even N nuclei in the rare earth region have been studied extensively both in experiment and theory (Bohr and Mottelson,1975). With the advent of in-beam γ-ray spectroscopy and sophisticated experimental and data analysis techniques, vast information on the lower and higher lying excited states have become available. The proton rich ^154-160Dy isotopes which is on midway between Z = 50-82 major shell closures span the spherical to the well deformed region. Chuu and Hsieh (1988) used IBM-1 and reproduced the energy spectra of the Dy isotopes but only the ground-band transition rates were calculated. Gupta et al., (1992) analyzed the six K-bands of ¹⁵⁸Dy by using the DPPQ model (Kumar, 1975). The present work represents an extensive analysis of the positive parity level structures in ¹⁵⁸Dy using IBM-1