Differences of deformation parameter<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>β</mml:mi></mml:math>for different transition mechanisms; comparison with data

Abstract

The differences between the isovector and isoscalar parts of the collective deformation parameter $\ensuremath{\beta}$ are obtained from the results of microscopic effective-charge theory. For single-closed-shell nuclei, differences, due to the isovector parts, of up to about 20% between ${\ensuremath{\beta}}_{n{n}^{\ensuremath{'}}}$ and ${\ensuremath{\beta}}_{p{p}^{\ensuremath{'}}}$ are predicted, ${\ensuremath{\beta}}_{n{n}^{\ensuremath{'}}}$ being much closer to ${\ensuremath{\beta}}_{\mathrm{em}}$ than to ${\ensuremath{\beta}}_{p{p}^{\ensuremath{'}}}$. Data on single-closed-shell nuclei are tabulated and their general trend supports our predictions.NUCLEAR REACTIONS ${0}^{+}$ \ensuremath{\rightarrow} ${2}^{+}$ transitions; estimate of ${\ensuremath{\beta}}_{2}$ deformation parameter---differences for different transition mechanisms; comparison with data.