|Message: De-excitation (problem) vs Hadronic Physics List||Not Logged In (login)|
Click on the Forum title, e.g. on the "Forums by Category" page, to read a sequence of postings to the Forum and its threads all in one page. If you are only interested in one thread or the thread following a specific posting, click the thread or the posting, which takes you to a smaller page, which contains only the part you are interested in and may be easier to navigate.
Messages are "chained" if there are only replies at the first level, i.e. 1/1.html, 1/1/1.html etc. In case of "chained" messages the message number is replaced by the icon and there is no indentation.
Inline: Display the subject line only or also the text of the posting(s); for the choice "All" the "Outline" choices are switched off.
|1||0||1||no text / full text of posting|
|2||1||All||text for level 1 only / text for All postings|
Outline: Choose the depth of the posting thread, successive toggle controls provide increasing detail.
|1||2||1||2 levels / 1 level (original posting)|
|2||3||2||3 levels / 2 levels|
|3||3||All||3 levels / all levels (all postings)|
Dear Hadronic Forum,
I have been working for some time on the reactions 235U(n, f) with neutron energies between 100 MeV and 1.0 GeV.
My simulations are based on the Hadr03 example of the version 9.6, but using a very thin target (0.00016 mm) of U235 and going to count the processes which take place in emission of fission fragments with mass "A" between 30 and 175.
For each energy I used a pencil beam of 10^9 neutrons. Each run (for each fixed energy) was repeated 6 times, varying the initial seed, in such a way as to have a mean value and a standard deviation of the value of the cross section.
I have used QGSP_BIC, FTFP_BERT, QGSP_INCLXX with neutron energies between 100 and 200 MeV, interval within which there are data in the literature: Nolte and Lisowski.
I am attaching the result of this work.
I know that INCLXX uses G4ExcitationHandler, as it is written in the Physics Reference Manual in Chapter 38, Section 38.1 page 514.
First question: Which model of de-excitation using BERT and BIC? In the Physics Reference Manual in Chapter 29, Section 29.2.6 page 447 it is written (for BERT) G4InuclEvaporation. Is it so? And for BIC?
Second question: From the graph you've attached, it is clear that within that range of energy INCLXX is better than BERT and BIC. Despite this, the experimental data are not in good agreement with those of the simulation.
A possible improvement of this comparison it could get (for example) going to change the level density parameter at the saddle point, which is described in Physics Reference Manual in Chapter 34, paragraph 34.4.1 on page 494.
But at this point, I need some of your advice: In what file can I change this value?
Third question: Do you think there are other possible parameters to be modified to increase the fission. If yes, which are they and where are they?
Thanks in advance Cheers
|Inline Depth:||Outline Depth:||Add message:|