Re: [fluka-discuss]: Problems with optical photons and roughness

From: Francesc Salvat-Pujol <francesc.salvat.pujol_at_cern.ch>
Date: Tue, 19 Feb 2019 18:34:11 +0100

Dear Alexey,

Sorry for the delay.

The surface roughness effectively applies a Gaussian spread on the
reflected direction, de facto acting as a convolution, which is a
norm-conserving operation. So one would in principle expect to obtain
the same integrated fluence (tracklength) in the region.

Could you submit a self-contained dataset with all necessary files to
reproduce your situation in both cases for further investigation? Did
the reflectivity change for some reason from one case to the other?

Cheers,

Cesc

On Fri, Feb 08 2019, at 18:04 +0000, Загороднюк Алексей А. wrote:
>
>Dear Fluka users,
>
>I am trying to model the propagation of optical photons in the NaI crystal. To make an estimation of total number of optical photons in the crystal I use USRBIN with only one region. It gives me the total track-length of optical photons in the specified region per incident particle. When I use smooth reflector with zero roughness the program gives me one result. But when I use reflector with roughness equal to 0.3 it gives me three times smaller result of total optical track-length in the region. It looks like roughness parameter eliminates photons during reflection. Can anyone tell me please is it normal result or I misunderstand the meaning of roughness in the program?
>
>
>Thank you in advance,
>
>Alexey

--
Francesc Salvat Pujol
CERN-EN/STI
CH-1211 Geneva 23
Switzerland
Tel: +41 22 76 64011
Fax: +41 22 76 69474
__________________________________________________________________________
You can manage unsubscription from this mailing list at https://www.fluka.org/fluka.php?id=acc_info
Received on Tue Feb 19 2019 - 19:56:08 CET

This archive was generated by hypermail 2.3.0 : Tue Feb 19 2019 - 19:56:39 CET