Re: [fluka-discuss]: simple photon-fluence calculation

From: <me_at_marychin.org>
Date: Thu, 9 Oct 2014 10:36:56 -0700 (PDT)

Dear Uwe,

We have different ways for estimating fluence:
- estimation by volume / region / cell (USRTRACK by track-length and USRCOLL by
number of collisions in FLUKA, F4 in MCNP);
- estimation by surface / boundary crossing (USRBDX in FLUKA, F2 in MCNP).

If you are referring to the default particle creation-loss table in the standard
MCNP output, the list we get is problem-wide. Those counters are not specific to
any volume or surface. They are counters (as in one, two, three, four, ... then
divide by total weight), not estimates. They have very little to do with
fluence.

If you want region / cell -specific counting of interaction types:
For FLUKA, go to ENTRY USRDRAW in mgdraw.f, where interaction types are
differentiated by ICODE.
For MCNP you would need PTRAC, then extract by NTYN and MTP.

MCNP does not provide 'volumentally (f4) for photon pair production, photon
capture, ...' Consider the meaning. Fluence is more an estimation rather than
literal counting (one, two, three, four, ...) Fluence is defined by particle
type (neutron fluence, photon fluence, ...) Fluence is not defined by
reaction/interaction type (pair production, capture, ...)

:) mary


> On 04 October 2014 at 11:49 "Uwe Riesterer (uwe.riesterer_at_hs-furtwangen.de)"
> <uwe.riesterer_at_hs-furtwangen.de> wrote:
>
>
> Dear FLUKA Experts.
>
> I work with Flair and try to simulate two nested spheres (r1=30cm, r2=50cm),
> one filled with water and the other with air.
>
> As result I would like a calculation of the photon-fluence from the outer air
> sphere, comes from a simple isotropic 14 MeV photon-beam from the middle.
>
> So my question:
>
> Is there an option similar to the “Volumentally (f4)” in MCNP5, which shows
> me the
>
> * photon tracks
>
> * photon loss
>
> * photon escape
>
> * photon pair production
>
> * photon capture
>
> * etc.
>
> just for my spherical target area? Or how do I get such a output?
>
>
>
> Thanks a lot for your help!!
>
> I´m just a beginner...
>
>
>
> ***************************************************
> Riesterer Uwe
>
> Furtwangen University of Applied Sciences
> Security & Safety Engineering
> ***************************************************
>
Received on Thu Oct 09 2014 - 21:08:57 CEST