Linear attenuation coefficient with DETECT card

Scoring
1

Versions

Please provide the used software versions.

FLUKA: fluka4-5.1
Flair:3.4-4

Description

Dear FLUKA experts,

I am a FLUKA beginner, I just started working on it three month later. I want to calculate mass attenuation coefficient of a glass according to the setup that they did experimentally. I looked up at first the same setup done in an article that I tried to reproduce the same in order to be sure of the results. The first issue is that after getting my outputs from DETECT card, I don’t know exactly what the four columns mean. How can I my intensities (I0 and I) like they did in order to get ln(I0/I) https://dergipark.org.tr/en/download/article-file/909916

I used to read a lot of post like Mass attenuation coefficient of a lead block - #7 by msacrist related to that issue but couldn’t find a solution to my issue.

In the same time, I tried to use USRBDX to the sample to score the entering photon to the sample as my I0 and the leaving photons as my I ( if I understood what this card does), and my outputs are almost empty and show a high rate of error. Do I define well my regions of scoring? What can I do to have a good value of attenuation in these cases?

I am looking forward to learn more about that. Any assistance will be helpful for me.

here the attached files

Input files

NaI.flair (3.0 KB)

NaI.inp (2.8 KB)

3

Dear Zissaya,

the easiest way to calculate I0/I ratio is to compare particle fluence/flux over the plane (surface) before and after the material. The USRBDX scoring in a Fluka dedicated to this purpose, see page 24 of the tutorial https://indico.cern.ch/event/694979/contributions/2927109/attachments/1657642/2654312/Scoring_2018.pdf

The advantage of this card is that you can get integrated values from the .lis output files.

The DETECTor is a more specific card (page 38), typically used for even or particle-specific detection of particles, so in my opinion, it is not convenient to use if your task is the calculation of the attenuation coefficient only. You can also use USRBIN, as you have it in your simulation, but pay attention that you will need to separate the required planes and find a way to calculate flux outside Fluka, or use region-type detectors.

I am not sure if I understand the question, but the last column in .lis file for the detectro output is the statistical error in percent.

I do not see technical problems with your model and configuration or USRBDX, but for the tasks described by you, I do not see reasons for EMFCUT and DETLARAY cards.

Kind regards,

Illia