Known mDOM geometry mismatches

[martinunland]

Here is a list of known geometric differences between the simulation and the actual module. These differences were initially assessed to have minimal impact, and implementing them in the simulation would require significant development time, therefore they were assigned low priority. As the validation campaign begins, any discrepancies between measurements and Monte Carlo simulations may need to be investigated, and these geometric differences should be reviewed.
These differences are listed in order of estimated impact:

• The equatorial reflectors in the actual module have cut sides, while in the simulation they are completely round
• The holding structure's position is now well-defined, as it is attached to a plate during production. The height in simulation and measurements should be verified. Note that the simulation currently assumes a uniform gel layer
• The holding structure is not 100% absorbent in reality, with significant color variation between prints. Could be important for flasher profile.
• The expansion joints of the holding structure are not implemented in the simulation

Additionally, there are features that should be correct but warrant verification:

• PMT tilt on the holding structure: The flexibility of the holding structure may have resulted in different angles after gel curing compared to the default design
• Reflector angles achieved during production should be measured and compared to simulation values