Elsevier

Nuclear Physics A

Volume 645, Issue 2, 11 January 1999, Pages 203-238
Nuclear Physics A

Transition state rates and mass asymmetric fission barriers of compound nuclei 90,94,98Mo

https://doi.org/10.1016/S0375-9474(98)00606-XGet rights and content

Abstract

Excitation functions were measured for complex fragments with atomic number Z = 5–25 emitted from the compound nuclei 90,94,98Mo produced in the reactions 78,82,86Kr + 12C. Mass-asymmetric fission barriers were extracted by fitting the excitation functions with a transition state formalism. The extracted barriers are several MeV higher on average than the calculations of the Rotating Finite-Range Model and substantially lower than predicted by the Rotating Liquid Drop Model. The symmetric fission barriers measured support the hypothesis of a congruence term that doubles for the fission of strongly indented saddle-point shapes. The excitation functions were analyzed to search for atomic number Z- and energy E-dependent deviations from transition-state-method predictions. All of the measured excitation functions can be scaled onto a single universal straight line according to the transition-state predictions. No Z- and/or E-dependent effects that could be attributed to transient effects are visible.

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  • Cited by (0)

    2

    McKinsey & Company, Inc., 301 Grant Street, Suite 2600, Pittsburgh, PA 15219-1414, USA

    3

    INFN, Via Amendola 173, 70126 Bari, Italy

    4

    Institut de Physique Nucleaire, Bat. 100, 91 406 Orsay cedex, France

    5

    Look Ease Enterprises Ltd., Dominion Centre, 43–45 Queen's Road East, Hong Kong

    6

    Syagen Technology, 1411 Warren Ave, Tustin, CA 92780, USA

    7

    X-Ray Instrumentation Associates, 2513 Charleston Road, Suite 207, Mountain View, CA 94043, USA

    8

    865 Carlisle Way, Sunnyvale, CA 94087, USA

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