[fluka-discuss]: Re: [fluka-discuss]: γ ray count problem using USRBDX

From: Anna Ferrari <a.ferrari_at_hzdr.de>
Date: Fri, 06 May 2016 11:09:02 +0200

Dear Tao Yang,

in addition to the very good suggestion of Mikhail I would like to point out
that you DON'T obtain zero with your USRBDX card associated to the boundary
vacuum/lead (LU 31)!!!
I ran your simulation, the point is that your obtain statistics only in the
last bin and maybe this confused you. Look at your tab/sum files (I put in
attachment what I obtained running your input): if you multiply the bin
content (directly in part/GeV per primary, because you did not specify the
area of the crossed surface) by the bin width, you get exactly 1 (well,
0.99999947 in my case, within my limited statistics).
So... the photons are going exactly where they have to go :-)

Kind regards,
Anna


Am Fri, 6 May 2016 09:21:24 +0800 (GMT+08:00) schrieb "YANG Tao"
<yangt_at_ihep.ac.cn>:
> Hello, everyone!
>
>
> I simulate the lead shielding effect for γ ray recently, but I got a strange
>result. Beam position is at (0,0,0) and the beam direction is in z-direction.
>The gamma rays were directed towards a simple cuboid lead block with 10.5 cm
>in thickness and 200cm*200cm in length and width. USRBDX score card has been
>used to obtain the transmission values, I/I0, where I0 and I are the incident
>and attenuated photon intensities. Theoretically, I0 is 1 photon/primary
>since the incident photon will all penetrate the front surface of the lead
>block, however, the result (31BIN, "rushe") always give ZERO result, it's
>confusing, where did the photons go? Additionly, the exit photon (32BIN,
>"chushe") also give a wrong results compared to other literature.
> These problems have confused me for several days, so any help will be
>appreciated much!!!
>
> Thank You!
>
> Tao Yang
>
> CAS

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Anna Ferrari
Institute of Radiation Physics
Helmholtz-Zentrum Dresden-Rossendorf e.V.
Tel. +49 351 260 2872
a.ferrari_at_hzdr.de
http://www.hzdr.de

Vorstand: Prof. Dr. Dr. h. c. Roland Sauerbrey, Prof. Dr. Dr. h. c. Peter
Joehnk
Vereinsregister: VR 1693 beim Amtsgericht Dresden



__________________________________________________________________________
You can manage unsubscription from this mailing list at https://www.fluka.org/fluka.php?id=acc_info

Received on Fri May 06 2016 - 12:50:22 CEST

This archive was generated by hypermail 2.3.0 : Fri May 06 2016 - 12:50:30 CEST