Dear Community
My name is David and I have the following problem:
Background
My goal is to compute the double differential photon fluence across a predefined interface between two regions. In addition, I would like to have a linear binning for both, the photon energy and the polar angle (not the solid angle).
Problem
To my best knowledge, USRBDX only offers angular binning in the solid angle. Therefore, I tried USRYIELD using the double differential fluence yield option (see attached input file below). Unfortunately, I couldn’t find a way to have a binning in both, the photon energy as well as the polar angle in the lab frame. It seems to me, that USRYIELD offers only the option to bin one out of the two variables (with multiple bins). For the other variable, one can define only 1 bin with lower and upper limit.
My brute force solution is – at least at the moment – to define multiple USRYIELD cards for each individual polar angle bin. My problem is know, that for my more complex problems (100 different interfaces, 5 degree bin width in the polar angle between 0 and 180 degree, 3 keV bin width in energy between 0 and 3072 keV), I would need to define 100*180/5=3600 USRYIELD cards.
Questions

Is there a builtin solution in FLAIR/FLUKA to perform the requested double differential fluence scoring with linear binning in the photon energy and the polar angle?

If the answer to question 1 is no, could you maybe point to a specific user routine and sketch a way how to alter the corresponding user routine?

Regarding my brute force method, is there maybe a nicer/easier way to write multiple USRYIELD cards in FLAIR, e.g. with preprocessor cards?
Attachment
For your convenience, I’m attaching here my toy problem with the brute force solution mentioned above:
USRYIELD_test.flair (5.8 KB)
USRYIELD_test.inp (5.0 KB)
To limit the number of USRYIELD cards for this toy problem, I applied a coarse binning in the polar angle (30 degree) and included only 1 scoring interface.
Thank you very much for your support
Kind regards,
David