Re: problems with 252Cf source

From: <>
Date: Fri, 22 Jun 2012 16:46:31 +0200 (CEST)

Dear User,
please next time include the input file and the user routines that you are
using. I suggest you to read the pdf in the attachments about the
customization of the user routines.

If you want to generate, for example, a uniform and isotropic fluence
inside a sphere, you can exploit the sflood routine of Fluka (as explained
in the pdf).

This subroutine
returns in XXX, YYY, ZZZ a random position ON the surface of a sphere
of radius 1 and center 0 (multiply XXX, YYY, ZZZ by the actual radius
and add the center coordinates) and UXXX, VYYY, WZZZ are radnom cosines
properly distributed so that to generate an uniform and isotropic
fluence inside the sphere (of course in absence of material inside the
sphere), numerically given by 1 / (pi R^2), R being the sphere radius.

I hope this helps,

> Dear experts,
> I want to model a source of Californium-252. Because of the complex
> energy spectrum and the isotropy a source routine is necessary. I
> found a source routine written and posted in November 2009 by Alberto
> Fasso. I compiled and linked it and inserted a SOURCE-card with the
> first WHAT set 1 in my input file and tried a simple sphere of vacuum,
> using an USRBIN-card for neutrons. The results do not match with my
> comprehension of an isotropic source, because there is only a beam in
> one direction. Changing the parameters in the BEAM and BEAMPOS cards,
> I couldn?t improve the results. Is there anything wrong in my input
> file? Is the use of the source routine the wrong approach?
> Looking forward to get helpful answers!
> Best regards
> Carolin

Received on Fri Jun 22 2012 - 19:02:14 CEST

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