Re: USRBIN neutron fluence

Dear Beatrice,

I would not expect a dramatic gradient in neutron fluence over the small
area you are pointing at. Anyway, actually it looks like you need to
increase your statistics in order to get a more reliable estimate. May be
resorting to importance biasing. (In your case, switching off the
electromagnetic transport does not lead to save much CPU time per
primary).

Ciao

Francesco

**************************************************
Francesco Cerutti
CERN-EN/STI
CH-1211 Geneva 23
Switzerland
tel. ++41 22 7678962
fax ++41 22 7668854

On Tue, 29 Mar 2011, beatrice pomaro wrote:

> Dear Fluka users,
> I give in attachmet my input file; the problem is the evaluation of
> neutron fluence on a concrete bunker shielding 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. It is a parallelepiped of
> dimension X: 3,5cm Y: 3,5cm Z: 7cm.
> The USRBIN cards investigate this volume with a resolution 0,2mm, in order
> to catch the thin zone around aggregates, which is 0,3mm order of
> thickness.
> I obtained the plots I give in attachment; I expected, however, to catch a
> different behavior of the materials corresponding to the aggregates and the
> thin area around them, because of different chemical composition and
> density.
>
> Do I have to better the statistics to have results more acceptable?
> Thank you
> kind 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 Sun Apr 03 2011 - 22:38:58 CEST