A high-spin isomer in 145 Sm was discovered by using Inverse kinematic reactions, 20 Ne e Xe,a7n) 145 Sm and 16 0 e 36 Xe,7n) 145 Sm. The half life was determined to be 0.96 J.LSec. Sixty-five 1-rays were identified by the /')'-coincidence measurements to belong to the isomer decay. The low-lying level scheme of 145 Sm was established in detail by the in-beam 1-ray measurements using the 139 La e 0 B,4n) 145 Sm reaction. A complex decay scheme of this isomer was constructed by using the data obtained from the 136 Xe induced reactions, combining the informations of low-lying states mentioned above. The excitation energy of this isomer was determined to be 8.8 MeV. The /')'-coincidence measurement using the 138 Ba (13 C,6n) 145 Sm reaction was also performed. Based on this information, the level scheme above the high-spin isomer was extended up to the state at 14.6 MeV. A 1-ray angular distribution measurement using the same reaction with pulsed beam was carried out and was used to assign a spin value of each level. Low-lying states in 145 Sm were interpreted to originate from a single neutron coupled to the 144 Sm core excitation. Experimental yrast states were compared with a calculation of a deformed independent particle model (DIPM). A configuration of the high-spin isomer was deduced by the DIPM calculation to be { 7r h ll /2 2 v (f 7 /2 h 9/2 i 13/2) } 49/2+ .

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Abstract. The fl+ decay of 86Mo has been firstly investigated by means of f17 spectroscopy. The 86Mo nuclei were produced by fusion-evaporation reactions of 54Fe (35C1, 1 p2n) and 58Ni (32S, 2p 2n) at beam energies of 103 and t20 MeV, respectively. Three 7 rays of 47.3, 49.8 and 187.0 keV were unambiguously identified to follow the fl+ decay of 86Mo by results of X7 and f17 coincidence and cross-bombardment. A half life and a maximum fl+-ray energy of 86Mo were determined to be 19.6_ 1.1 s and 3.9_+ 0.4 MeV, respectively. A decay scheme of 86Mo is proposed in this article. Furthermore, a decay of S6Nb has been studied using the same combinations of projectiles and targets, and a new fl-decaying isomer 86mNb was observed with a half life of 56.3 _+ 8.3 s.

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