Re: dpdx=<0 problem in isotope user written source simulation

Dear Nicholas,
CC: FLUKA discussion,

Thank you very much for your suggestion.
It's true that FLUKA runs if energy is divided by 1000. However, I
intentionally input such highly energetic source particles. (e.g. 1st
particle is 18.18 GeV (371MeV/a) V-49.). Do you know why FLUKA refuses
to read 18.18 GeV source?

As for the number of lines, I was going to modify it in the true (not
test) runs.

Any ideas on source particle energy are appreciated.

Sincerely,
Ogawa

(2010/09/07 1:05), Nicholas Bolibruch wrote:
> Your source routine is inputting MeV level energies as GeV (
> 18.1824493218291 MeV being read as 18.1824493218291 GeV) from the data
> file. Of course this is assuming the kinetic energies sampled from the
> source file are supposed to be in MeV....
>
> Just modify the line:
>
> TKEFLK (NPFLKA) = energy(sample)
>
> to be
>
> TKEFLK(NPFLKA) = energy(sample)/1000D0;
>
> Once this was done, the simulation ran without any issue.
>
> Also, I don't know if this part is deliberate, but your source routine
> only reads 149 lines from the data file, but there's 200 lines in the file.
>
> Hope this answers your question!
>
>
> Cheers,
>
> Nicholas Bolibruch
>
>
> On 01/09/2010 9:08 PM, Ogawa Tatsuhiko wrote:
>> Dear FLUKA experts,
>>
>> I am trying to transport isotopes using a user written source. But I
>> don't know why it crashes saying
>>
>> Stepop, dp/dx=<0!! ij, z, a, mmat, ekin, pthrmx, dpdx0 -2 23 49 6 0.6
>> 7.80517436 -543.194742
>> Abort called from STEPOP reason dp/dx=<0 Run stopped!
>> STOP dp/dx=<0
>>
>> in .err file.
>>
>> This happened regardless of WHAT(1) of BEAM card.
>> It seems to have something to do with source energy because when I
>> overwrite source kinetic energy (for example 18.1824493218291 -> 0.50),
>> it runs.
>>
>> I would appreciate if someone could help me to run this simulation.
>>
>>
>> Please find the attached files if necessary.
>>
>> coll.inp: input file
>> source_frag.f: modified source.f file. Source file directory is defined
>> in the 71st line.
>> iso-source.dat: source information. the columns are atomic number, mass
>> number, x,y,z coordinates, x,y,z angular cosines, kinetic energy (not
>> divided by the number of nucleons), statistical weight, respectively
>> from left to right.
>>
>> Many thanks in advance,
>> Ogawa
>>
>>
>
>
Received on Tue Sep 07 2010 - 11:21:33 CEST