Isotopic yield in cold binary fission of even–even 244–258Cf isotopes

Abstract

The cold binary fission of even-even [244][245][246][247][248][249][250][251][252][253][254][255][256][257][258] Cf isotopes has been studied by taking the interacting barrier as the sum of Coulomb and proximity potential. The favorable fragment combinations are obtained from the cold valley plot (plot of driving potential vs. mass number of fragments) and by calculating the yield for charge minimized fragments. It is found that highest yield for 244,246,248 Cf isotopes are for the fragments with isotope of Pb (Z=82) as one fragment, whereas for 250 Cf and 252 Cf isotopes the highest yield is for the fragments with isotope of Hg (Z=80) as one fragment. In the case of 254,256,258 Cf isotopes the highest yield is for the fragments with Sn (Z=50) as one fragment. Thus, the fragment combinations with maximum yield reveal the role of doubly magic and near doubly magic nuclei in binary fission. It is found that asymmetric splitting is favoured for Cf isotopes with mass number A < 250 and symmetric splitting is favoured for Cf isotopes with A > 252. In the case of Cf isotope with A=252, there is an equal probability for asymmetric and symmetric splitting. The individual yields obtained for the cold fission of 252 Cf isotope are compared with the experimental data taken from the γ-γ-γ coincidences technique using Gammasphere.

Mass yield of spontaneous fission of 238 U within the systematic statistical scission-point model

“…Researchers have usually calculated the spontaneous fission half-lives [46][47][48] and Relative mass yields [21,23,49] for even-even elements with WKB model. In one of the modified statistical scission-point mode [18], the mass yield values are significantly different compared to the experimental data (more than 0.03).…”

“…The fission fragments mass yields were calculated using the WKB approximation model for spontaneous fission [20,21], cold fission [22,23] and ternary fission [24,25] of super-heavy nuclei and Actinides. Recently, Gao [26] calculated the spontaneous fission half-lives for heavy and super-heavy nuclei by applying a new method of numerically solving Schrödinger equation.…”

Deformation parameter changes in fission mass yields within the systematic statistical scission-point model

“…The extremum values of energy at the scission point is usually used to find the atomic numbers of the fission fragments [36][37][38][39]. The exponential function is upward-sloping, so the minimum total energy at the scission point has the greatest effect in equation (2).…”

Investigations on Fission of Compound Nuclei with Z=120

“…Based on the liquid drop model, Bohr and Wheeler [2] developed the theory of fission. Over many years, it has been clearly observed that lowenergy fission of heavy elements with Z > 90 is one of the most complicated nuclear processes [3]. Andersson et al [4] investigated binary fission of 159 Tb and nat Ag induced by 600MeV protons, finding fission yield cross sections of 1.9mb and 1.0mb, respectively.…”

“…Fig 3. Plot of logarithmic half-lives for isotopes of nuclei 298−300,302 120 as a function of fission fragment mass number A 1…”