Level structure of ¹¹⁶Sn and ¹¹⁷Sn from (p, d), (p, t) and (p, p′) reactions

Abstract

The level structure of ¹¹⁶Sn has been investigated by the reactions ¹¹⁷Sn(p, d), ¹¹⁸Sn(p, t), and ¹¹⁶Sn(p, p′) with 55 MeV incident protons and that of ¹¹⁷Sn by ¹¹⁸Sn(p, d) and ¹¹⁷Sn(p, p′) reactions. The emitted particles have been analysed with a broad-range magnetic spectrometer. Angular distributions of emitted particles in the (p, d), (p, t) and (p, p′) reactions are analysed in terms of the DWBA method. A strong similarity between the ¹¹⁷Sn(p, d) and ¹¹⁸Sn(p, t) reactions is found in the excitation of all of the observed states in ¹¹⁶Sn. Three new 2⁺ states in ¹¹⁸Sn are identified both from the (p, d) and (p, t), and two excited 0⁺ states are established. Spectroscopic factors for 25 states extracted from the ^{117, 118}Sn (p, d) reactions are compared with theoretical predictions based on the pairing interaction plus quadrupole-quadrupole and octupole-octupole interactions. The agreement is reasonably good except for the 2⁺ states at E_x ≈ 4 MeV in ¹¹⁶Sn.