Re: On biasing

Dear Dr. Sala,
      thank you for your help; I see one has to assign different
importance factors to different regions, but I can not understand the
criterion to do that.
On the other hand, would you, please, explain to me better how to do
practically point 1) use higher e.m. thresholds in regions far from
the scoring one and point 3) use biasing to kill particles that
travel deep in the shield.
Thank you again,
Sincerely
Beatrice

At 15.48 10/05/2011, Paola Sala wrote:
>Dear Beatrice
>sorry, but I do not have brilliant, or even simple, ideas for your case.
>If I understand correctly your geometry, your region of interest is on the
>surface of the shielding, directly in front of the target. seen the beam
>energy, I assume that the beam is stopped in the target.
>Therefore, you do not have a deep penetration problem, where the biasing
>card (or equivalent) would be useful.
> By the way, how the biasing card is used in your input is meaningless:
>importanmce biasing works by splitting ok killing particles according to
>the relative importance of regions: if all regions have the same
>importance nothing happens.
>My only suggestion is to try to speed up the problem: use higher e.m.
>thresholds in regions far from the scoring one, use a thinner shielding or
>use biasing to kill particles that travel deep in the shield.
>Ciao
>Paola
>
>
>
> >
> > Dear Fluka experts,
> > I would like to put forward a problem in biasing. My problem
> > is in attachment: the geometry is a concrete room around a UC2
> > target. Near the point of coordinates (400, 500, 370) a small portion
> > of the concrete shielding is created at a mesoscale: aggregates and
> > paste. Results of neutron flux and energy deposition are reported as
> > well. I guess with biasing I can better my results, that is I can get
> > no more neutron tracks but more homogeneous contours; which biasing
> > technique should I apply? I tried to use the card but maybe you can
> > suggest which is the most suitable way to do that because I am not
> > that expert on biasing results.
> > Thank you for your help,
> > my best regards,
> > Beatrice
> >
> > **************************************************
> > Ing. Beatrice Pomaro
> >
> > Universita' degli Studi di Padova
> > Dipartimento di Costruzioni e Trasporti
> > Via F. Marzolo, 9 - 35131 Padova (Italy)
> > tel.: +39 049 8275605
> > e-mail: pomaro_at_dic.unipd.it
> >
> >
Received on Wed May 11 2011 - 11:34:05 CEST