Resolve "mass treatment in CS shower"

Description

This branch was used for the latest developments in AHADIC which are now finalised - this merge would update master to the version that Gurpreet tunes/tuned.

Test Plan

Run the code with Gurpreets Tune results and compare with the original version.

Example Result

See Tune

Additional Checklist Items

• I have updated documentation as needed

Closes #314 (closed)