Present status and future aspects of nuclear structure close to "1"0"0Sn

The present status of experimental approach to "1"0"0Sn in the spectroscopy of excited states is landmarked by the T_z=3/2 nuclei between "9"5Pd and "1"0"1In and the T_z=1 nuclei "9"4Pd and "9"8Cd. The detection limits with Pre-EUROBALL #gamma#-arrays and ancillary detectors are below the 10"-"5 level of the total fusion - evaporation residue cross section. A large scale shell model analysis of the existing data reveals the shell structure at "1"0"0Sn, which shows a remarkable similarity to "5"6Ni. Evidence for an increasing proton-neutron interaction in approaching the N=Z line is deduced from high spin isomers and spherical yrast lines. The effective E2 operator for protons and neutrons and implications for a low lying particle-hole (ph) E2 excitation in "1"0"0Sn are discussed. (orig.)SIGLEAvailable from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

"9"8_4_8Cd_5_0 - The two-proton hole spectrum in "1"0"0_5_0Sn_5_0

Excited states in "9"8Cd, two proton holes from "1"0"0Sn, were identified and studied for the first time, using in-beam spectroscopy with highly selective ancillary detectors. The structure of the (#pi#g_9_/_2)"-"2 two proton hole spectrum below a T_1_/_2=0.48(16) #mu#s isomer is deduced and compared to shell model predictions. A tentative I"#pi#=(8"+) assignment, as suggested by systematics, yields a strongly reduced B(E2.8"+#->#6"+)=0.44(_-_1_0"+"2"0) W.u., corresponding to an effective proton charge of #epsilon#_#pi#=0.85(_-_1_0"+"2"0) #epsilon#, which is at variance with existing theoretical predictions. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman