Studies on the decay of high-spin isomers in the W and Os isotopes

From the two experiments performed on the nucleus 180Os the properties of the new high-spin isomer could be found. The excitation energy amounts to 5208 keV and the spin of the isomer amounts probably to I=19ℎ. The new measured half-life amounts to T1/2=41±10 ns. It is populated with an intensity of 1.6±0.4% relative to the (4 + → 2 +) transition in the Yrast band in an experiment with out use of the recoil-shadow technique. A preliminary decay scheme could be established from the sum spectra and exhibits similarities with the decay of the high-spin isomer in 182Os. From the analysis of the experiment on the nucleus 178W a new isomer with an excitation energy of 5271 keV and a half-life of T1/2=39±10 ns could be identified. The spin of the level has been determined to I=20±1. The half-life of the 3527 keV isomer has been determined to T1/2=28±4 ns. The spin of the isomer could be determined from the analysis of DCO ratios to Iπ=14-. The configuration of the isomer could be fixed to ν6 + 5/2 -55127 x 7/2 55147 +π8 - 7/2 +54047 x 9/2 55147 because of the comparison with the 14- isomer in 176Hf and the comparison of the excitation energy for certain configurations with Iπ=14-. (orig./HSI)