Single-Particle Neutron Bound States in Iron Isotopes and in Cobalt Studied with (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>p</mml:mi><mml:mo>,</mml:mo><mml:mi> </mml:mi><mml:mi>d</mml:mi></mml:math>) Reactions

Abstract

The energy spectra of deuterons from ($p, d$) reactions in ${\mathrm{Fe}}^{54}$, ${\mathrm{Fe}}^{56}$, ${\mathrm{Fe}}^{57}$, ${\mathrm{Fe}}^{58}$, and ${\mathrm{Co}}^{59}$ targets were experimentally measured and angular distributions obtained for the more prominent deuteron groups. Reduced widths for exciting various final states differ widely from state to state. The deuteron groups corresponding to the strongly excited states have angular distributions which fit distorted-wave calculations for angular momentum changes of one and of three units. The energies of these groups progress systematically through the sequence of isotopes, and an attempt is made to interpret the groups in terms of single-particle neutron bound states. Definite evidence for strong residual interactions is observed. The locations and number of states suggest the applicability of the Nilsson model with the assumption that ${\mathrm{Fe}}^{54}$ and ${\mathrm{Co}}^{59}$ are spherical and that ${\mathrm{Fe}}^{56}$, ${\mathrm{Fe}}^{57}$, and ${\mathrm{Fe}}^{58}$ are deformed in a prolate configuration.