supercritical mass

supercritical mass

[¦sü·pər′krid·ə·kəl ′mas]
(nucleonics)
A mass of nuclear-reactor fuel whose effective multiplication factor is greater than 1.
References in periodicals archive ?
With the full flight of the uranium <<projectile>> into the uranium <<target>>, a supercritical mass of nuclear explosive was formed, in which a chain nuclear reaction of an explosive nature was initiated by means of a neutron fuse (external source of neutrons).
Scientists needed a fundamentally new technical solution to create and undermine the supercritical mass of the nuclear charge of an atomic bomb from weapons-grade plutonium [94.sup.239]Pu [9, 11].
To trigger nuclear fission reactions in weapons-grade plutonium [94.sup.239]Pu with the supercritical mass obtained, a neutron flux initiating them was needed.