Search

Using the (a,n) reaction, the half-life of the first 11/2- level in97Mo has been determined as T1/2(1437.0 keV)=2.5±0.3 ns by means of the pulsed beam method. The experimentally obtainedB(M2) value between theh11/2 andg7/2 configurations in97Mo has been satisfactorily described within the quasiparticle-phonon model usinggseff=0.6gsfree. Similar calculations and comparisons with experminental data have been performed also for95,99Mo as well as for99Ru and101Pd.

By means of the generalized centroid-shift method, the following half-lives were determined:T1/2(3045 keV)=3.7±0.3 ns in113Sb using the reaction104Pd(12C,p2n) as well asT1/2 (1322.8 keV)=3.5±0.3 ns,T1/2(2779.8 keV) =0.50±0.15ns,T1/2(2874.9 keV)<0.2 ns andT1/2(3072.9 keV)<0.1 ns in117Sb using the116In(a, 2n) reaction. Three-quasiparticle configurations of the type pd5/2?(h11/2d3/2) in113,117Sb are found to dominate in the wave functions of the 19/2- states at 3045 and 2780 keV in113Sb and117Sb, respectively. TheB(E2, 19/2- ? 15/2-) values in113–119Sb are discussed.

The nucleus107In was studied by in-beam spectroscopic methods in (HI, xn yp) reactions. Spin and parity values of some levels were determined by conversion electron and?-ray measurements. Using the generalized centroid shift method, the half-lives T1/2(19/2+, 2003.6 keV)=0.6±0.2 ns and T1/2(17/2+, 1853.4 keV)=1.7±0.3 ns were measured. The systematics of the lowest members of the multipletpg92/-1×61+ in111,109,107In is discussed

Applying the generalized centroid shift method in the142Nd(a, 2n)144Sm reaction the following half-lives have been measured:T1/2(3,376 keV)=(1.6±0.2) ns,T1/2(3,460 keV) =(0.5±0.2) ns andT1/2(5,150 keV)?0.3 ns. Level energies and electromagnetic transition rates have been calculated within a particle-core coupling approach that is based on the shell model with configuration mixing. The persistence ofl-forbiddenness of M1 transitions between rather complex configurations could be confirmed.

Bombarding a85Rb target by 27 MeVa-particles the following half-lives of excited states in different nuclei have been determined by means of the generalized controid shift method: in87Y,T1/2(2827.1 keV)=0.75±0.10 ns,T1/2(2675.9 keV)=0.25±0.10 ns,T1/2(3595.3 keV)=0.5±0.2 ns andT1/2(2986.9, 3094.4 keV)<0.1 ns; in88Y,T1/2(232.1 keV)=0.8±0.1 ns and in85Rb,T1/2(151.2 keV)=0.6±0.1 ns. In87Y, the members of the doublet (vg92/-2)8+ (pp1/2) are identified. E2 transition rates 21/2+? 17/2+ in odd A˜ 90 nuclei are shown to represent essentially core transitions. Evidence for the existence of seniority-five configurations is found.

The half-life of a 3- excited state in106Ag was measured as T1/2 (364.4 keV)=0.9±0.1 ns using the103Rh(a, n)106Ag reaction. The intramultiplet transition rate B(M1, 3-?2-) indicates that the configuration p(g9/2)0-2p(p1/2)-1 vd5/2 can be assigned. A low-lying 3+ isomer, as known in108,110Ag, was not found in106Ag, what is explained by the raising energy of the vd3/2 shell with decreasing neutron number. For the 6- bandhead of a rotational-like structure T1/2 (765.2 keV)< 0.2 ns was derived in contradiction to an earlier prediction (200 ns). Indirect evidence for a negative sign of the magnetic moment of105Ag (g.s.) is obtained.