From: Ing. Alessandro A. Porta (porta@nuclearmi.cesnef.polimi.it)
Date: Tue Mar 04 2008 - 16:28:26 CET
Dear Sebastien, you're right, however since the DETECT card normalizes
results you should simply read the value in the full-energy peak channel.
I use a very useful binning of about 1 keV / channel in the DETECT card.
You can read DIRECTLY the absolute efficiency in the last useful (non zero)
bin.
Sometime you'll need to use the last two bins, due to the discretization
effect, it occurs whenever you'll see two values of the same magnitude. In
that case the efficiency comes from the sum of such two bins.
So, each energy requires it's simulation... anyway it's not a problem if you
can work with a computing cluster ;-)))))
This method could appear tedious but is capable of simulating any HPGe and
matrix !
Moreover, you can couple the HPGe geometry with voxel matrices and much
more...
You can see attached two examples: Cd-109 which requires only 1 bin and
Te-123m which requires to sum the last two bins to get the "real"
efficiency.
Best regards
Alessandro
______________________________________________
«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Alessandro A. Porta, Ing., EQ III, Ph.D.
CESNEF - Politecnico di Milano
Via Ponzio 34/3 - 20133 Milano - Italy
ph.: +39-02-2399-6365 / 6300
fax. +39-02-2399-6309
e-mail: alessandro.porta@polimi.it
URL: http://www.radioprotezione.polimi.it
______________________________________________
«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> -----Messaggio originale-----
> Da: Sebastien WURTH [mailto:wurth@ipno.in2p3.fr]
> Inviato: martedì 4 marzo 2008 14.56
> A: Ing. Alessandro A. Porta
> Cc: fluka-discuss@fluka.org
> Oggetto: Re: to Sebastien, it could be useful: Example-HPGe.doc
>
> Hello Alessandro, hello everyone,
>
> It is very useful indeed, thank you very much for sharing this.
> It is still mysterious to me how you calculate your efficiency from
> DETECT card. Is it as I assume, a ratio between the counts in your
> detector at the energy you want divided by the number of primaries which
> represents here the number of events delivered by the source ?
> I use a very simple example which has nothing to do with a real case
> (compared to yours).
> But I use the same set of defaults as you, put my EMF-CUT cards,
> PHYSICS, EVENTYPE cards like yours (just in case), of course no biasing,
> and I have still that sort of stopping power effect in my DETECT card.
> My first purpose : I only wanted to see if these physical effects took
> place, ie the peak of efficiency at energies ~100-150 keV. I think I
> should see this, even with my trivial sample with an isotropic point
> source at 10 cm centered around a Ge cylinder circular face. With values
> which won't mean anything, but I should have the same curve as in your
> document, shouldn't I ?
>
> I keep on searching...
>
> Best regards.
> Sebastien.
>
> Ing. Alessandro A. Porta a wrote :
>
> >This is a very simple but efficient example about an HPGe chrystal
"sampled"
> >vith a DETECT card.
> >It works very well since years (... for me, at least...).
> >
> >Hope it could be useful.
> >
> >Best regards.
> >
> >Alessandro
> >
> >______________________________________________
> > «¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤
> >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >Alessandro A. Porta, Ing., EQ III, Ph.D.
> >CESNEF - Politecnico di Milano
> >Via Ponzio 34/3 - 20133 Milano - Italy
> >ph.: +39-02-2399-6365 / 6300
> >fax. +39-02-2399-6309
> >e-mail: alessandro.porta@polimi.it
> >URL: http://www.radioprotezione.polimi.it
> >______________________________________________
> > «¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤»§«¤»¥«¤
> >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> >
> >
This archive was generated by hypermail 2.1.6 : Wed Mar 05 2008 - 11:57:08 CET