Modeling a Blackbody Spectrum in FLUKA

Source Definition
1

Versions

Please provide the used software versions.

FLUKA: 3.4-5.2
Flair:

Description

Hello all,

I am trying to model a blackbody emitter in flair and score the photon counts on a detector. I think I’ve got the detector modeling down, but how would I model the source? Lets say I am modeling something like the sun’s emission spectrum seen at sea level, is there a way to properly do this in flair? Or do I need to write a source routine or something like that, if so, could I get some literature on that?

Here’s an image to better visualize what I mean by a blackbody spectrum emitted by the sun. I am trying to emit a large, continuous, spectrum of photons over an area.
(This is to measure UV photons of a specific range for a senior capstone project for background on a detector)

Any help is appreciated! The attached input file is our simulated thorium source and the UV-fluorescence it causes being measured by some PMTs at varying distances, if theres any improvements I can make there let me know!

image
image1280×960 108 KB

Please describe the issue. In case of reporting a bug, please provide step-by-step instructions for reproducing the error.

Input files

Please upload all relevant files. (FLUKA input file, Flair project file, user routines, and data files)

ButtonTH-230.inp (3.5 KB)

3

Dear Daniel,

Thank you for your question.

From a conceptual viewpoint, you could write a source routine in which you set the energy of your optical photon according to the desired distribution. If you have a mathematical formulation describing the spectrum, you could use it directly for sampling. Sampling from a histogram of the same distribution would be another possible approach.

Here you will find some material to get started with source routines:

Regarding the physics of the simulation itself, please make sure to check the current capabilities and limitations of FLUKA for optical photons. The following material should help clarify them:

Hope this helps,

Tommaso

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