Re: [fluka-discuss]: muon production frm gamma conversion or positron annhilation

From: Alberto Fasso' <fasso_at_slac.stanford.edu>
Date: Mon, 11 Nov 2013 03:06:52 -0800 (PST)

Production of photomuons in FLUKA and G4 is implemented according to
different theories:
- in FLUKA, according to Tsai, Rev. Mod. Phys. 46, 815 (1974)
- in G4, according to Kelner, Kokoulin and Petrukhin, CERN-SL-2002-016 (2002)

In the absence of experimental data, the fact that FLUKA results differ from
those of G4 can mean one of three things:

1) Fluka results are not correct
2) G4 results are not correct
3) Both Fluka and G4 results are not correct.

Unless a good benchmark is provided, nobody may say that anyone of
the three statements above is true.

Anyway, I can tell you the following about the FLUKA model:
- the same model has been implemented in the MUCARLO code of L. Keller and in
   the MARS code of N. Mokhov
- no benchmark is available about muon spectra, but measured doses have been
   well reproduced by both FLUKA and MARS, as reported in:
   Code benchmark of muon flux after a several meters of iron from 14 and 18 GeV
   electron induced reactions in forward direction
   T.Sanami, W.R.Nelson and N.V.Mokhov
   SLAC Radiation Physics Note, RP-07-15 (2007)
- measured muon doses have been well predicted by FLUKA at the SLAC LCLS
   machine

Unfortunately, I am not aware of any similar benchmark done with G4. If you
know some, I would be interested to know.
Of course, the benchmarks I have mentioned do not refer to spectra but
only to doses. So the above points 1) to 3) can still all be true.

Alberto

On Mon, 11 Nov 2013, belgin piliçer wrote:

> Ok. Not measured but I found a study which is simulated with G4. 
> I mean Fluka result is not the same with G4 so I said that it is not
> correct.
> Maybe I overlook something.
>
>
>
>
>
>
> 2013/11/11 Alberto Fasso' <fasso_at_slac.stanford.edu>
> How do you know that "it is not correct spectrum"? Do you have
> available
> a measured spectrum?
>
> Alberto
>
> On Sun, 10 Nov 2013, belgin piliçer wrote:
>
> Hello experts,
> I attached my input file. Now muon production is possible
> but  it is not
> correct spectrum. 
>
> Thanks for your advance.
> b.
Received on Mon Nov 11 2013 - 13:13:17 CET