Re: Dose point kernel and electron ranges

Dear Jean-Emmanuel

surely the boundaries between the shells are disturbing the correct
elctron propagation if the shells are very narrow. One obvious
solution is to force single scattering everywhere with the MULSOPT
option, or (it should be enough) to force single scattering every time
the conditions for multiple scattering are not met
(eg MULSOPT with what(4)=1, what(5)=1, what(6)=1, or 2000 for single
scattering everywhere, sdum=GLOBEMF)

In general one should avoid to introduce fictitiouos boundaries
particularly if they are very close one to another.

However the lack of a spherical user binning makes it hard to do
otherwise...

                      Ciao
                     Alfredo

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On Tue, 11 Dec 2012, Jean-Emmanuel Groetz wrote:

> Dear Fluka experts,
>
> I would like to calculate the dose point kernel (DPK) around an
> isotropic electron point source in concentric water shells. We have
> chosen four energies: 10, 30, 50 and 100 keV. Radial binning is quite
> small, ie 1/120 of the RCSDA (continuous slowing down approximation
> range).
> Results at 50 and 100 keV seem to be good, compared to others codes, but
> at 10 and 30 keV, large discrepancies can be observed. Due to the very
> small thickness of the concentric shells of water, I am wondering if
> some options like MULSOPT or STEPSIZE must be activated or not.
> This kind of problem is most certainly addressed in the paper in Medical
> Physics (2011) with fluka authors, but I could not get it in due time.
>
> Thank you in advance for your help.
> Jean-Emmanuel
>
> --
> _______________________________________________
> Jean-Emmanuel Groetz
> Laboratoire Chrono-Environnement UMR CNRS 6249
> Chimie-Physique & Rayonnements
> Universit?? de Franche-Comt??
> 16 route de Gray
> 25030 Besan??on Cedex
> France
>
> mailto : jegroetz_at_univ-fcomte.fr
> tel : +33 (0) 3 81 66 65 07
> fax : +33 (0) 3 81 66 65 22
> _______________________________________________
>
>
>
>
Received on Tue Dec 11 2012 - 17:40:58 CET