Dear Paola and Vasilis,
Thank you very much for your responses to both of you.
I now understand that the transport threshold does not apply in vacuum and production thresholds does not apply to nuclear interaction and decays.
I also understand that Auger and internal conversion electrons will be produced even if I cut photons, and secondary electrons coming from photons will not be produced.
Everything is now clear for me.
Thank you again for your help.
Best regards,
Thomas Frosio
-----Original Message-----
From: Paola Sala [mailto:paola.sala_at_mi.infn.it]
Sent: Tuesday, September 12, 2017 11:21 AM
To: Thomas Frosio <thomas.frosio_at_cern.ch>
Cc: fluka-discuss_at_fluka.org
Subject: Re: [fluka-discuss]: RE: Score monoenergetic electrons and removing photons for source calculation
Hello
just one specification:
Production thresholds do NOT apply to nuclear interactions and nuclear decays. X, Gamma rays, beta and auger electrons will be in any case produced. They could be immediately "dumped" on spot if the TRANSPORT threshold is higher than their energy.
As Vasilis said, transport thresholds do NOT apply in vacuum, otherwise there could be energy deposition in vacuum, that is a nonsense.
Thus, setting a very high transport threshold for photons will cause:
- in air: all photons stopped at the production point, their energy deposited there
- in vacuum: photons will fly up to the next region (air?) and stop immediately after the boundary.
Also:
The production/transport threshold for photons has no direct effect on electrons and vice-versa. There is an non-direct effect, of course: if photons are killed, they will not produce secondary electrons.
Hope this helps
Paola
> Hi Thomas,
>
> I told you the inverse for the thresholds in vacuum.
> Since you cannot deposit energy in the vacuum the transport threshold
> doesn't apply, while of course the production can apply as I mentioned
> before after a decay.
>
> Cheers
> Vasilis
>
> ________________________________
> From: owner-fluka-discuss_at_mi.infn.it [owner-fluka-discuss_at_mi.infn.it]
> on behalf of Vasilis Vlachoudis [Vasilis.Vlachoudis_at_cern.ch]
> Sent: Monday, September 11, 2017 17:56
> To: Thomas Frosio; fluka-discuss_at_fluka.org
> Subject: [fluka-discuss]: RE: Score monoenergetic electrons and
> removing photons for source calculation
>
> Hi Thomas,
>
> if you put a high threshold for both production and transport in
> EMFCUT (for the decay part) nothing will be generated nor transported.
> You can try to put a low threshold for production and a high for
> transport so the electrons will be generated and killed immediately.
>
> Vacuum is special, no interaction can happen there (apart decays) so
> the production threshold do not apply, while the transport threshold
> should be applied, which seems is not the case.
> Maybe is it not checked after a source particle is generated. I will
> try to check.
>
> Cheers
> Vasilis
>
> ________________________________
> From: owner-fluka-discuss_at_mi.infn.it [owner-fluka-discuss_at_mi.infn.it]
> on behalf of Thomas Frosio [thomas.frosio_at_cern.ch]
> Sent: Wednesday, September 06, 2017 16:04
> To: fluka-discuss_at_fluka.org
> Subject: [fluka-discuss]: Score monoenergetic electrons and removing
> photons for source calculation
>
> Dear FLUKA expert,
>
> I am with the volonty to compute E+/E- fluences related to a source in
> my geometry.
> In radioactive sources:
> 1 - Electrons/positrons can be produced directly by the source,
> continuously with the spectrum or discretly by internal conversion or
> Auger,
> 2 - Photons are emitted and interact with the environment outside the
> source, giving movement to electrons.
> I would like to remove electrons produced by process 2 and I want to
> keep Auger electrons and internal conversion electrons.
>
> My question concerns how are Auger and Internal Conversion simulated
> in the code:
> If I add an EMFCUT card, putting for example a threshold of 10TeV for
> photons in all my geometry, will Auger and IC electrons be simulated?
> In other terms, simulation of monoenergetic electrons in Fluka is
> linked with photon simulation or is there a description of
> probabililty to emit monoenergetic electrons directly in the source data?
>
>
> I have a second question.
> I made a simple input with a source of Tb156 cutting photons
> everywhere in the geometry until 10TeV.
> This source is inside vacuum. And this vacuum is in air.
> I used USRBDX score to check there is no photon passing from vacuum to
> air.
> Unfortunately, I observe a photon fluence.
> But if I replace vacuum by air, there is no fluence.
> Is there a reason for this ?
> The input is attached with the photon fluence.
>
>
> I thank you for your answer,
> Best regards,
> Thomas Frosio
>
>
Paola Sala
INFN Milano
tel. Milano +39-0250317374
tel. CERN +41-227679148
__________________________________________________________________________
You can manage unsubscription from this mailing list at
https://www.fluka.org/fluka.php?id¬c_info
Received on Tue Sep 12 2017 - 18:23:06 CEST