Spectroscopy of nuclei around ${}^{100}$Sn populated via two-neutron knockout reactions

Abstract

We report on the in-beam gamma spectroscopy of ${}^{102}$Sn and ${}^{100}$Cd produced via two-neutron removal from carbon and CH${}_2$ targets at about 150 MeV/nucleon beam energy. New transitions assigned to the decay of a second 2${}^{+}$ excited state at 2470(60) keV in ${}^{102}$Sn were observed. Two-neutron removal cross sections from ${}^{104}$Sn and ${}^{102}$Cd have been extracted. The enhanced cross section to the 2${}_2^{+}$ in ${}^{102}$Sn populated via the $(p,p2n)$ reaction is traced back to an increase of shell-model structure overlaps, consistent with the hypothesis that the proton-induced two-deeply-bound-nucleon removal mechanism is of direct nature.