Neutron-capture gamma rays from $sup 116$Sn and $sup 122$Sn and the valence model

Capture $gamma$-ray intensities from resonances of $sup 116$Sn and $sup 122$Sn have been measured. The results lead to binding energies of 6944 +- 2.0 keV for the product nucleus $sup 117$Sn and 5948 +- 3.0 keV for the product nucleus $sup 123$Sn. Resonance spins were determined: in $sup 116$Sn, E$sub 0$ = 147.9 and E$sub 0$ = 632 eV resonances are J = 3/2, l=1; $sup 122$Sn, E$sub 0$ = 106.9 eV resonance is J = 3/2, l = 1; E$sub 0$ = 259.9 eV resonance is J = 1/2, l = 1. The measured partial widths are compared to single-particle transition model predictions. The model fails to predict the observed widths. (AIP)