Light-charged particle emission in fission

An Evaporation-Based Model of Thermal Neutron Induced Ternary Fission of Plutonium

“…(23) with particle binding energies estimated using Eqs. (3)(4)(5)(6)(7)9) as discussed in section II (see table I or model I in table II). The model parameters are then adjusted to minimize the fitting metric defined in Eq.…”

“…The main ternary-fission observables include the probability per fission event of generating various isotopes, their energy spectra and angular distributions. Extensive measurements of these properties have been made and substantially documented in several review articles [3][4][5][6]. The dominant ternary-fission particles are α particles, which occur a few times per thousand thermal-neutron-induced or spontaneous fissions.…”

“…Ternary fission is thus often referred to as near-scission emission. There is a very rare process that generates a third light charged fragment in the fission process close to the direction of motion of the main two fission fragments [5,6]. This is often called polar emission.…”

Systematics of pre- and near-scissionα-particle multiplicities in heavy-ion-induced fusion-fission reactions

“…Although there have been many studies on prescission α-particle emission in many heavy-ion-induced fusion-fission reactions [1,2,[5][6][7][8][9], a global systematics is yet to be developed. In low-energy fission (thermal neutron-induced, photo-, and spontaneous fission) NSE is a dominant channel [11][12][13] and exhibits characteristic energy and angular distributions corresponding to strong focusing of the particles by the Coulomb field of the fragments. The near-scission α-particle multiplicities are found to increase linearly with Z 2 /A of the fissioning nucleus [11,12].…”

“…In low-energy fission (thermal neutron-induced, photo-, and spontaneous fission) NSE is a dominant channel [11][12][13] and exhibits characteristic energy and angular distributions corresponding to strong focusing of the particles by the Coulomb field of the fragments. The near-scission α-particle multiplicities are found to increase linearly with Z 2 /A of the fissioning nucleus [11,12]. The features of the NSE observed in low-energy fission have been understood qualitatively with the sudden neck collapse dynamic model suggested by Halpern [13].…”