The particle asymmetric rotor descriptions of187?193Ir positive parity states

The asymmetric rotator model applied to odd-mass Iridium isotopes

“…Fifteen levels are known [2,3,[6][7][8] with confidence and there exist two previous quantitative attempts to describe them either in the axial [7] or triaxial scheme [15]. Hence it is interesting to compare the quality of their fits with ours obtained using the assumptions COR 2B, TRI 2K and TRI 3K.…”

“…Table 2 gives the values of the goodness of the fit for different approaches. It would be better to compare g' instead of g but if it is easy to fix p to 5,5 and 6 respectively for our different assumptions, it is not clear how many parameters can be considered as really free in the other approaches: at least 2 in [15] and at least 4 in [7]. Anyhow, we see from Table 2 (columns 4 and 5) that if it is not possible to distinguish between the two (direct and inverse) axial approaches, it is however evident that the triaxial shape is preferred.…”

“…The observed levels have generally been arranged into two rotational bands. Previous qualitative or semi-quantitative interpretations have been given in [6,7,12,15]. On the one hand Andr6 et al [6,7] have made classical Coriolis coupling calculations in the frame of an axial nucleus.…”

“…On the other hand Vieu etal. [15] made a detailed analysis of the positive parity levels within an extended version of the Hecht and Satchler model [12]. Even by introducing several intrinsic states in their calculation they could only obtain a qualitative description of the energy spectra.…”

“…More recently Vieu etal. [15] extended this approach to several intrinsic configurations in order to explain the positive parity states. All these approaches lead however to agreement between experimental and theoretical spectra the quality of which is much less impressive than that generally obtained in the well deformed rare earth region.…”