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Quenching of the MQ transition strengths in inelastic scattering to 6" states in 28 Si is predicted when the a\/ 2 shell-model space is enlarged to include the s\/2 single-particle orbital. Nucleon transfer cross sections to the yrast (/, T) = (6 ", 0) and (6', 1) states and B (Ml) between them are also predicted to decrease when the extended space is used. The calculations suggest that the data may be understood in terms of only nucleon degrees of freedom once an adequate model space is used.PACS numbers: 23.20. Ck, 21.60.Cs, 25.80.Fm In both the (Id,2s) and l/ 7/2 shells inelastic scattering experiments 1 " 6 on even-even nuclei populating the high-spin "stretched" magnetic states have cross sections very much smaller than predicted by the (^5/2*)^ [dg^"" 1 ®/,/^-. T and (A/ 2 n )-* [/ 7/2 ' 1 " 1 (8)^9/ 2 ] 8 -; r models. This has led to the speculation that nonnucleonic degrees of freedom may have to be introduced to account for the observed quenching. In this note, we examine the effect of increasing the size of the model space and show that, for 28 Si, the inclusion of the 2s 1/2 single-particle level substantially reduces the predicted cross sections. Other properties of these 6" levels are examined and, in all cases, use of the larger space improves the agreement between theory and experiment. Although significant deviations from experimental results still exist, the calculations suggest that when a still larger model space is used the remaining discrepancies may become small.The simplest model of 28 Si is one in which the 0 + ground state is described by the configuration (^5/2 12 )/=o;r = o and the (A? 1 ) = ( 6~> 0) anc * (6",1) states have the form [d 5/2 n £)/ 7/2 ] / = 6 -. r . With this model one predicts equal matrix elements for the transition operator [a 7 / 2;1 / 2 *® a 5 / 2;1 / 2 ] 6M . T0 which governs inelastic scattering between the ground state and these two 6" levels,

A shell model calculation for the states of 91Tc has been carried out using the (lg9/2, 2pl/2 ) model space with residual interactions determined from previous studies and assuming that Z = 38 N--50 is a closed shell. The results, both for the spectrum and the gamma decay modes, support the experimental angular momentum assignments made for the high spin states. The predicted binding energy of the 9/2 + ground state relative to 88Sr is within 75 keV of the experimental value and the calculated excitation energy of the 1/2-state is 183 keV. There is only one instance where theory and experiment disagree: the highest energy excited state, the 41/2-at 7.715MeV, is predicted to undergo quadrupole decay to the 37/2-and this decay mode is not seen.