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arXiv · 1106.6240

Identification of the slow E3 transition 136mCs -> 136Cs with conversion electrons

Abstract

We performed at ISOLDE the spectroscopy of the decay of the 8- isomer in 136Cs by and conversion-electron detection. For the first time the excitation energy of the isomer and the multipolarity of its decay have been measured. The half-life of the isomeric state was remeasured to T1/2 = 17.5(2) s. This isomer decays via a very slow 518 keV E3 transition to the ground state. In addition to this, a much weaker decay branch via a 413 keV M4 and a subsequent 105 keV E2 transition has been found. Thus we have found a new level at 105 keV with spin 4+ between the isomeric and the ground state. The results are discussed in comparison to shell model calculations.

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K. Wimmer, U. Koester, P. Hoff, Th. Kroell, R. Kruecken, R. Lutter, H. Mach, Th. Morgan, S. Sarkar, M. Saha Sarkar, W. Schwerdtfeger, P. C. Srivastava, P. G. Thirolf, P. Van Isacker. 2011-06-30. Identification of the slow E3 transition 136mCs -> 136Cs with conversion electrons. https://doi.org/10.1103/physrevc.84.014329%2010.1103%2Fphysrevc.84.029903

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