fission barrier

fission barrier

[′fish·ən ‚bar·ē·ər]
(nuclear physics)
One or more maxima in the plot of potential energy against nuclear deformation of a heavy nucleus, which inhibits spontaneous fission of the nucleus.
References in periodicals archive ?
In modeling fission, physicists think of a nucleus as residing in a valley of low potential energy; to fission, the nucleus must "tunnel" through a neighboring hill known as the fission barrier. The excited actinide nuclei, it was determined, don't sit at the bottom of the valley, but rather in a little crevice farther up the fission hill.