Draft: RICH in RUN3 using DD4HEP and Gaussino from Jan12-2024

This contains the RICH detector simulation package named GaussPhotonics in the new framework. This branch is created from lhcb-sim11-dev as of Jan05-2024.

This package creates the MC hits and a few other output classes from the RICH system which are then written to sim files. An example of the ‘options file’ used for running this and an example of the run log file (compressed) are attached here for reference.

This package is intended for the simulation of the RICH in RUN3 only. It has the protections implemented regarding ‘RICH specific’ optical processes. As a result, any other subdetector in RUN3 can use different optical processes and there will be no interference between the simulation of RICH and the simulation of the other subdetector.

As in the past, this stores various information in the output, including the track segments through each RICH. They are useful for various RICH reconstruction studies including those being done using emulated tracks for RUN5 these days. However, the RICH system in RUN5 is envisaged to be a brand new detector with several new features and there are many options that are being considered. Therefore, this new RICH system will be simulated in a new package as part of the RUN5 studies so that, the current package for RUN3 will be essentially unaffected by those developments.

Integration of the RICH simulation into Gauss involves updating some of the python configuration scripts in the Gauss area. This branch contains those updates also. These are made starting from those in the master version of Gauss on Jan05-2024. So far these scripts seem to evolve a lot in the master area. This may result in this branch becoming often out of sync with the master branch. In this context, occasionally attempts will be made to update these scripts in this branch to avoid this issue.