PARTICLE-HOLE INDUCED ELECTRIC AND MAGNETIC ROTATION IN IN-111

The high-spin structure of In-111 has been investigated with gamma-ray spectroscopic methods using the Zr-96(F-19,4n) reaction with thin and backed targets. A comprehensive level scheme has been constructed whi ch exhibits interesting collective as well as novel single-particle ex citations. Unambiguous evidence of proton particle-hole excitations is found for the first time in a Z<50 nucleus in the form of decoupled b ands involving proton g(7/2)(d(5/2)) and h(11/2) orbitals above the Z= 50 spherical shell gap. The high-spin structure of In-111 also involve s the recently discovered magnetic rotation mechanism which is manifes t as high-spin Delta I=1 bands with no signature splitting and large B (M1) strengths, but only a small associated deformation. [S0556-2813(9 8)03604-8].