Dear expert
I use resnucle card to calculate the activity of 20MeV,50μA proton bombardment tungsten target 10 min,the total activity in tungsten is higher than the literature results ,could you please help me find my mistakes?
the result of literature as shown in the figure below,it should be about1.6GBq,I calculated the results for 0 hours
The geometric dimension of probe is 30mm × 28 mm × 2 mm,the pulse shape of proton beam is Gaussian distribution in X,Y direction, and the half height width is 1 mm and 3 mm respectively. The average intensity of proton beam is about 50uA
after a first quick glance you do not seem to be simulating what you actually want to simulate. Please have a look at the beam definition in your input!
In addition, I would suggest to activate the coalescence model for activation calculations. Check out the PHYSICS card in the manual.
Dear Chris Theisctheis
Sorry,I changed the upload file,about beam card, I uploaded the wrong file before。And I use the EVAPORAT parameter in PHYSICS card。
In the end,about the output lis file,should the activity of isomers be considered? I found that the activity of isomers is much greater than that of other nuclides。
in addition to the EVAPORATION card it is suggested to activate also COALESCENCE via an additional physics card. You can define several physics cards.
I cannot judge on your specific problem and the comparison to literature that you are trying to do. But I can only suggest that you make sure that the parameters on which your literature data is based is modeled as closely as possible. So if they consider meta stable states in their total activity then you should also do this. If they do not, which sometimes is the case, then you should not. In the .lis file of FLUKA they are taken into account.
You should also make sure that you are comparing the same cooling time. In your case with t=0 you will of course also see very high numbers for short lived isotopes like Re-183m which has a half-live in the range of ms.
Generally, make sure that you know those parameters (irradiation, cooling, geometry, etc.) of your literature data well because otherwise you might not be able to make meaningful comparisons.
Dear Chris Theisctheis
Thank you for your advice,I’ve tried to use activate also COALESCENCE in an additional physics card,but the difference between the results is very small。From the literature, the cooling time is 0,maybe I should check with the author of this paper。
Finally, I want to confirm with you that should the activity of isomers be considered when I calculate the induced radioactivity? Thank you for your kind advice
I am not sure that I understand what you mean. In principle, if you want to be “as close as possible” to reality then you should consider isomers.
Please note that in general total activity is not a very good quantity to do a comparison as there can be over- and under-compensation, outliers of specific reactions that will considerably influence the final value etc., that is practically impossible to understand from an integral quantity. In general it probably makes more sense to compare activities of specific isotopes.