Dear Vasilis
Thanks for your answer. I still have some doubts in that matter and would like to address them with an example. In particular, your statement that the tabulation becomes coarser when using a higher threshold.
I have a source routine which samples starting particles from thermal energies up to 100 TeV. When I set now the WHAT(1) of the beam card to 100 TeV does it cause then a tabulation binning being too coarse in the low-energy range (e.g. 100 MeV)? My interest in that matter (tabulation of cross sections) goes primarily to activation of matter.
Thanks again for the re-iteration of the problem.
Best regards
Helmut
From: Vasilis Vlachoudis
Sent: 27 March 2014 09:08
To: Helmut Vincke; fluka-discuss (fluka-discuss_at_fluka.org)
Subject: RE: What (1) parameter of BEAM
Hi Helmut,
you correctly guessed. All tabulations of cross sections, dE/dx, etc... are calculated from the minimum threshold defined in your
input and/or from the DEFAULTS up to the energy defined in the BEAM what(1) + 10% (if I remember well).
So if you put a lower value than your source.f routine, you will make the code crashing most probably with a dp/dx < 0 (negative!)
If you set it too high you will get both unnecessary tabulations, longer initialization time and more coarser.
dE/dx tabulations you can control and print them with the EMFFIX, FLUKAFIX
Best Regards
Vasilis Vlachoudis
Dep EN, CERN
CH-1211 GENEVA 23
SWITZERLAND
Phone: +41-22 767 9851
GSM: +41-76 487 4378
Fax: +41-22 766 9644
________________________________
From: owner-fluka-discuss_at_mi.infn.it<mailto:owner-fluka-discuss_at_mi.infn.it> [owner-fluka-discuss_at_mi.infn.it] on behalf of Helmut Vincke [Helmut.Vincke_at_cern.ch]
Sent: 26 March 2014 17:46
To: fluka-discuss (fluka-discuss_at_fluka.org<mailto:fluka-discuss_at_fluka.org>)
Subject: [fluka-discuss]: What (1) parameter of BEAM
Dear FLUKA users and authors
Can someone provide me with a bit more information about the mandatory need of WHAT(1) of the BEAM card (in case I sample my primary particles via a source.f routine). The manual says:
(command BEAM<
http://www.fluka.org/fluka.php?id=man_onl&sub=12> not requested): not allowed! The WHAT(1) value of the
BEAM<
http://www.fluka.org/fluka.php?id=man_onl&sub=12> command is imperatively required, in order to set up the
maximum energy of cross-section tabulations.
What kind of cross sections are tabulated and how does it refer to the energy/momentum set in WHAT(1)?
Is it a problem for the accuracy of the run when setting the WHAT(1) to 100 TeV and sampling primary particles only in the GeV range? I would be grateful if you could give me some indications if the granularity of the cross-section tabulation is a function of the WHAT(1) parameter or if a higher WHAT(1) value just increases the number of cross sections tabulated for the run.
Thanks in advance.
Best regards
Helmut
Received on Thu Mar 27 2014 - 10:48:02 CET