scholarly journals Point-by-Point model description of average prompt neutron data as a function of total kinetic energy of fission fragments

2013 ◽  
Vol 42 ◽  
pp. 07007 ◽  
Author(s):  
A. Tudora
2018 ◽  
Vol 169 ◽  
pp. 00006 ◽  
Author(s):  
Patrick Jaffke ◽  
Peter Möller ◽  
Ionel Stetcu ◽  
Patrick Talou ◽  
Christelle Schmitt

We implement fission fragment yields, calculated using Brownian shape-motion on a macroscopic-microscopic potential energy surface in six dimensions, into the Hauser-Feshbach statistical decay code CGMF. This combination allows us to test the impact of utilizing theoretically-calculated fission fragment yields on the subsequent prompt neutron and γ-ray emission. We draw connections between the fragment yields and the total kinetic energy TKE of the fission fragments and demonstrate that the use of calculated yields can introduce a difference in the 〈TKE〉 and, thus, the prompt neutron multiplicity v, as compared with experimental fragment yields. We deduce the uncertainty on the 〈TKE〉 and v from this procedure and identify possible applications.


2020 ◽  
Vol 15 (02) ◽  
pp. P02008-P02008
Author(s):  
A. Pal ◽  
S. Santra ◽  
A. Kundu ◽  
D. Chattopadhyay ◽  
A. Jhingan ◽  
...  

2018 ◽  
Vol 169 ◽  
pp. 00027 ◽  
Author(s):  
Mark D. Usang ◽  
Fedir A. Ivanyuk ◽  
Chikako Ishizuka ◽  
Satoshi Chiba ◽  
Joachim A. Maruhn

We have extended the Langevin equations to 4 dimensions (4D) by allowing the independent deformation for the left (δ1) and right fragments (δ2) of the fissioning nucleus. At the moment we are only able to use them in conjunction with the macroscopic transport coefficients. Nevertheless, we can see a considerable improvement in the preliminary results for the fission observables, especially those related to the total kinetic energy (TKE) of fission fragments. By plotting the TKE distributions we have revealed the super-long fission modes in 236U and super-short fission modes in 257Fm. By plotting the distribution of δ against the fragment’s TKE we have noted a correlation between the values of δ and Brosa’s fission modes. We have found that the standard fission modes correspond to prolate tips of the light fragments while the complementary heavy fragments have oblate fission tips. On the other hand, if both fragments were prolate at the tips, we get super-long fission modes. If both fragments were oblate at the tips, we get super-short fission modes.


2018 ◽  
Vol 169 ◽  
pp. 00011
Author(s):  
Vitaly Khryachkov ◽  
Andrei Goverdovskii ◽  
Vladimir Ketlerov ◽  
Vecheslav Mitrofanov ◽  
Alexei Sergachev

Binary fission of 232Th and 238U induced by fast neutrons were under intent investigation in the IPPE during recent years. These measurements were performed with a twin ionization chamber with Frisch grids. Signals from the detector were digitized for further processing with a specially developed software. It results in information of kinetic energies, masses, directions and Bragg curves of registered fission fragments. Total statistics of a few million fission events were collected during each experiment. It was discovered that for several combinations of fission fragment masses their total kinetic energy was very close to total free energy of the fissioning system. The probability of such fission events for the fast neutron induced fission was found to be much higher than for spontaneous fission of 252Cf and thermal neutron induced fission of 235U. For experiments with 238U target the energy of incident neutrons were 5 MeV and 6.5 MeV. Close analysis of dependence of fission fragment distribution on compound nucleus excitation energy gave us some explanation of the phenomenon. It could be a process in highly excited compound nucleus which leads the fissioning system from the scission point into the fusion valley with high probability.


1971 ◽  
Vol 24 (4) ◽  
pp. 821 ◽  
Author(s):  
JW Boldeman ◽  
AR de L Musgrove ◽  
RL Walsh

Measurements have been made of prompt neutron emission in the thermal neutron fission of 235 U and the mean neutron emission per fragment has been obtained for particular values of the fragment mass and total kinetic energy. A direct neutron counting method was employed and a comparison is made with data from previous experiments of this type.


2020 ◽  
Vol 242 ◽  
pp. 03004
Author(s):  
Satoshi Chiba ◽  
Mark D. Usang ◽  
Chikako Ishizuka ◽  
Fedir Ivanyuk ◽  
Zhang Xuan

Systematic and anomalous trends in fragment mass and TKE (total kinetic energy) distributions are investigated in terms of 4D Langevin model developed at Tokyo Tech. We have found that correlated transitions in symmetric components and dominant modes (symmetric v.s. asymmetric) can explain the prominent systematic and anomalous features of fission observables. We have also elucidated that interplay between spherical and deformed magicity at A=132 and A=142 to 144 is important in both observables.


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