From: John Clem (clem@bartol.udel.edu)
Date: Sun Jun 13 2004 - 20:09:27 CEST
It has been my understanding the maximum step size in a non-vacuum
region without a field should not be greater than ~ 1/3 of its minimum
dimension to allow the multiple-scattering routines to work properly.
This is briefly discussed in the documentation under STEPSIZE
John
On Sat, 12 Jun 2004, Paolo MAESTRO wrote:
>
> Hi Fluka users,
> I simulated a sampling calorimeter
> made of tungsten layers (0.35 cm thick)
> alternated with planes made of 0.05 cm thick scintillator.
> I noticed that protons (150 GeV kin. energy),
> passing through the detector as minimum ionizing particles,
> deposit energy in each scintillator plane only at the end of
> the considered region at the boundary with the next region.
> To explain better, if a scintillator plane extends
> from z= -0.35cm to z=-0.4 cm
> , dumping the energy deposit in MGDRAW & ENDRAW
> subroutine of mgdraw.f, it turns out that
> the deposit is recorded at z=-0.4 cm, i.e.
> at the boundary with the next tungsten layer.
> This has no physical meaning, and I guess it depends from
> the fact that the step size is bigger than the considered region
> thickness. I tried to set by hand a step size for the scintillators planes
> using the STEPSIZE options and it seems working well.
> But I wonder:
> - which is the empirical rule to set the min and max stepsize ?
> (I tried min = 1/50 scintillator thickness and max = 1/10)
> - in my case, do I need to set STEPSIZE also for tungsten layers?
> - is this procedure to avoid the energy deposit at boundaries correct ?
>
>
> Many thanks for your help.
> Best regards
>
> Paolo Maestro
>
>
>
>
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