Excited states of nuclei in the vicinity of Sn-100 have been studied using:
the EUROBALL detector array. Gamma-ray lines from Sn-103 have been identif
ied for the first time, and a level scheme of low-lying excited states of S
n-103 has been established. New constraints on energies of single particle
orbitals with respect to the Sn-100 core are obtained.