Replace scintillation time clipping by truncation

[HenningSE]

What does the code in this PR do / what does it improve?

This PR will replace the s1 photon timing clipping by truncation.

Can you briefly describe how it works?

Right now we are clipping the sampled S1 photon scintillation times in the S1PhotonPropagation plugin to the maximum value of maximum_recombination_time. To minimize the effect on the S1 waveform, this PR replaces the clipping by a truncation of the timing distribution at he same maximum_recombination_time. Two safety measures are added to make sure that we always have enough photon times to sample from. As a bonus the S1PhotonPropagation.photon_timings function was cleaned up and the scintillation timing part moved to a dedicated function.

Please include the following if applicable:

• Bump plugin version(s)
• Tests to check the (new) code is working as desired.

[coveralls]

Pull Request Test Coverage Report for Build 9193566598

Details

• 20 of 21 (95.24%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.06%) to 78.07%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
fuse/plugins/detector_physics/s1_photon_propagation.py	20	21	95.24%

Totals
Change from base Build 9139577908:	0.06%
Covered Lines:	2314
Relevant Lines:	2964

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💛 - Coveralls

[HenningSE]

A note discussing the proposed changes can be found here.

[ramirezdiego]

This looks good! Like previously discussed, I prefer this re-iterative loop than assigning times for many more photons than needed, based on a safety factor. Is there a speed improvement this way?

[HenningSE]

Hi @ramirezdiego, I think there is a slight performance increase using the code in this PR compared to the main branch. I did not run detailed performance tests but for the simulations done in the note above the raw records simulation time decreased by about 10%. Maybe this is not relevant to the overall simulation time when S2s are also included.

[ramirezdiego]

Thanks, I was actually just curious about the improved speed with respect to the previous approach in this PR.