Using isotope shift for testing nuclear theory: the case of nobelium isotopes

Abstract: We calculate field isotope shifts for nobelium atoms using nuclear charge distributions which come from different nuclear models. We demonstrate that comparing calculated isotope shifts with experiment can serve as a testing ground for nuclear theories. It also provides a way of extracting parameters of nuclear charge distribution beyond nuclear RMS radius, e.g. parameter of quadrupole deformation $\beta$. We argue that previous interpretation of the isotope measurements in terms of $\delta \langle r^2 \rangle$ between $^{252,254}$No isotopes should be amended when nuclear deformation is taken into account. We calculate isotope shifts for other known isotopes and for hypothetically metastable isotope $^{286}$No for which the predictions of nuclear models differ substantially.