Study of Heavy-Ion-Induced Reactions on Uranium with Use of Mica Detectors

Direct Evidence for Multiple Sequential Fission in the Interaction ofPb208andGottschalk1, Vater2, Becker3 et al. 1979Phys. Rev. Lett.Self Cite

“…Distorted-wave Born-approximation (DWBA) 1 analyses of some of the available medium-energy (~ 1 GeV) proton-nucleus inelastic differential cross-section data were found generally to give good overall agreement for both shapes and magnitudes of the cross sections, using spin-independent collective form factors and deformation lengths consistent with averages of results of 9 P 0 -A. Gottschalk et al, to be published. 10 S. Cohen, F. Plasil, and W a J 0 Swiatecki, Ann.…”

“…1 "" 3 The reaction mechanism expected to account for most of these multibody events is the sequential process: In a first step two primary fragments are formed after a quasielastic or deep-inelastic interaction and one or both subsequently fission as isolated nuclei. 4 Alternative reaction mechanisms could be instantaneous fission induced by Coulomb or nuclear forces 5 or multibody breakup after fusion.…”

Further Applications of Track Detectors and Some Directions for the Future

“…The energy resolution for each particle was good (~ 1%, fwhm), but charge discrimination (based on the growth rate of the track diameter with etching time) was rather poor. The method could not distinguish between 3 He and 4 He of the same range (but different energies), though giving the detector a suitable annealing treatment before etching did help in this respect.…”

“…Brandt and co-workers [2][3][4][5][6] have used mica detectors to examine ternary and quaternary fission in heavy elements, especially uranium, induced by very heavy ions such as 84 Kr,136 Xe, or 2 3 8 U. Such heavy projectile ions register tracks of their own, even in mica; but since they are normally-incident on the mica, they are revealed as small dots, and the fragments resulting from fission can be readily picked out (see Fig.…”