Low-Lying States inSb122from theSn

Abstract

The low-lying level structure of Sb is studied through the observation of coincident y rays following the Sn(p, n) reaction using two Ge(Li) detectors. Thirteen 1024-channel coincidence y-ray spectra were obtained simultaneously in a PDP-7 computer by means of a two-parameter program. High-resolution singles spectra taken with a small-volume thinwindow Ge(Li) detector (full width at half maximum approximately 0.6 keV at 121 keV) were also helpf'ul in determining a level scheme for Sb. A (d,p) experiment was also performed in order to gain additional information. The information obtained from the (p, n) reaction was combined with existing~Sb(d, p) and~Sb(n, y) data in constructing a proposed level scheme for Sb.

Properties of the low-lying levels of122Sb

“…Elliot etal. [8]. Levels not contained in Shera's level scheme and differing placements of y-rays will be discussed together with the assignment of spin and parity values.…”

“…Nevertheless, we have tried to find most probable J~ values for all levels to enable a comparison with the following calculation. The information available from (d, p) and (d, t) reactions [8,9] has not been used in the J~ assignments because the energy resolution achieved in these measurements didn't seem satisfactory. On the other hand, no obvious disagreement between our J~ values and the 1, values proposed by Hjorth [-9] can be recognized.…”

“…The single-particle energies are given in MeV. The occupation probability v~ is determined by solving the gap equations (8,7) state at 164keV, no high-spin members of the (re g 7/2, v h 11/2) and (re d 5/2, v h 11/2) multiplets are observed in the experiment. A high resolution measurement of the cross sections for one-neutron transfer reactions might reveal the positions of these states.…”

“…Gamma spectra from capture of thermal neutrons ( [3] and other references quoted in [4]) as well as from neutron capture in resonances [-5, 6, 7] have been investigated by several groups. Also 7-energies and 7-7 coincidences have been studied populating levels of 122Sb by the (p, n) reaction [8]. The level scheme of *Z2Sb as given in Nuclear Data Sheets [4] is essentially due to the (n, 7) investigations of Shera [3].…”

A study of the121,123Sb(p, d) reactions

“…Summaries of the levels of 12~ can be found in various compilations [4][5][6]. However, the 121Sb(d, t) [9], t23Sb(d, t) [9,10], and t21Sb(d,p) [9,10] single-neutron transfer reactions have also been studied, albeit with rather poor resolution and only at a few angles (No angular distributions at all are reported in [10]). [7] and the 121Sb(n, 7)iZ2Sb study of Alexeev et al [8].…”