Dear Emilio,
The problem is in the combination of an ISOTOPE beam with the USRYIELD
cards. USRYIELD calculates angular quantities with respect to the
direction of the beam, and since some of the quantities can be
calculated with respect to the center-of-mass frame, the code tries to
initialize a center-of-mass momentum, which fails if the beam momentum
is zero.
I have a question and a solution, besides that this specific situation
will be
protected in a next respin
Question: are you sure that you need USRYIELD instead of USRBDX? I
mean, what is the purpose of calculating angles with respect to a
fixed (beam) direction when source and geometry are perfectly
isotropic? Why not to use USRBDX that calculates angles with respect
to the normal to the boundary surface? (see note 1 to the USRYIELD
description in the manual)
Solution, in case you really need USRYIELD: add another USRYIELD card
with SDUM=BEAMDEF (see again note 1) , in order to define a dummy beam
just to initialize the scoring. For instance
USRYIELD PROTON 1.0 1. 0. 0. 1.0 BEAMDEF
Again from the fluka manual, USRYIELD description:
For SDUM = BEAMDEF:
WHAT(1) = projectile particle index, or corresponding name
Default= IJBEAM (beam particle)
WHAT(2)= target particle index, or corresponding name (used by the
code to define the c.m.s. frame)
Default : 1.0 (proton)
WHAT(3) = projectile momentum
Default= PBEAM (beam momentum)
WHAT(4,5,6) = projectile direction cosines
Default = UBEAM, VBEAM, WBEAM (beam direction cosines)
Hope this helps
Paola
On 7/21/22 06:44, emilio wrote:
>
> Dear Fluka experts,
>
>
> I am trying to simulate the decay of radioactive isotopes, however
> when I try to run the got (via Flair), i got a time-out error and no
> output is produced.
>
>
> In the attached file you can find the input card; I do believe however
> that the issue is in the primary particle generation.
>
> The radioactive isotopes are created with the following BEAM card
> (which is similar to the one I found here:
> https://indico.cern.ch/event/604018/contributions/2435668/attachments/1395470/2242783/19_Activation_2017.pdf)
>
>
> BEAM ISOTOPE
> HI-PROPE 34. 83.
>
>
> The RADDECAY card is present as well (semi-analogue mode)
>
>
> At first I thought the problem was that the isotopes are created at
> rest, so I changed the energy to 1 keV, but I got the same result.
> However if I try to change particle (for example, using electrons) the
> code runs without problem.
>
>
> Any idea where could be the issue?
>
> Thank you very much for your help
>
> Best Regards
>
> Emilio Ciuffoli
>
>
>
>
__________________________________________________________________________
You can manage unsubscription from this mailing list at
https://www.fluka.org/fluka.php?id=acc_info
Received on Thu Jul 21 2022 - 13:00:04 CEST