Signature effects in Gallagher-Moszkowski doublets of doubly odd 162, 164Ho and 164Tm nuclei

Abstract

The signature effects in total five Gallagher-Moszkowski (GM) doublets, three based on the $ K^{\pi} = 1^{-}$ ( ↑ ↓ ) , $ K^{\pi} = 6^{-} (\uparrow \uparrow):7/2[523]_{\pi} \otimes 5/2[642]_{\nu}$ configuration observed in 162 Ho, 164 Ho, 164 Tm nuclides and two based on the $ K^{\pi} = 1^{+} (\uparrow \uparrow)$ , $ K^{\pi} = 6^{+} (\uparrow \downarrow): 7/2[523]_{\pi} \otimes 5/2[523]_{\nu}$ configuration observed in 162 Ho, 164 Ho nuclides, are studied in the framework of two quasiparticle axially symmetric rotor model. We successfully explained the experimentally observed signature splitting and also confirmed tentatively assigned spin, parity and configuration assignments to some members of the GM doublets under discussion. For the $ K^{\pi} = 1^{-} (\uparrow \downarrow): 7/2[523]_{\pi}\otimes 5/2[642]_{\nu}$ member of the GM doublet observed in 164 Tm, the experimental phase of staggering before and after the point of inversion, which could not be explained in the earlier calculations, is successfully reproduced. The Newby shifted $ K = 0$ bands, which play a vital role in explaining the observed signature effects in the low-K members of the GM doublets under discussion, are identified and the corresponding Newby shift energies for these K = 0 bands are estimated. The lower-lying levels of some low-K members of the above-said GM doublets are not observed experimentally. The excitation energies of these unobserved lower-lying levels are calculated and presented as a future prediction for experimentalists.