Dose point kernel and electron ranges

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

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Jean-Emmanuel Groetz
Laboratoire Chrono-Environnement UMR CNRS 6249
Chimie-Physique & Rayonnements
Université de Franche-Comté
16 route de Gray
25030 Besançon Cedex
France
mailto : jegroetz_at_univ-fcomte.fr
tel : +33 (0) 3 81 66 65 07
fax : +33 (0) 3 81 66 65 22
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