Resolve "Detailed Dual RICH implementation"

A very preliminary dRICh is implemented. There is still room for improvement of the optics, but this geometry represents a decent starting point.

Because this MR is so long, careful attention was made to keep up-to-date with the master branch; the majority of final changes this MR brings are additions only.

Summary of changes in this MR:

• updates to athena.xml:
  • include compact/drich.xml in athena.xml, replacing the gaseous RICH
• updates to compact/definitions.xml, to be consistent with latest integration plans (as of 8/3/21)
  • ForwardRICH_lenth changed from 110 cm to 180 cm
  • ForwardTracking_length changed from 0 cm to 25 cm
• updates to compact/display.xml:
  • added some visual properties specific to dRICh; not necessary, but useful; they are colored similar to the ATHENA logo
• updates to compact/materials.xml:
  • add SiliconDioxide material; this is because the present material SiliconOxide, which has the same composition, has a different density (2.65 g/cm3) that what is found for G4_SILICON_DIOXIDE in Geant4 (2.32 g/cm3) (https://github.com/Geant4/geant4/blob/6399a014b611a4aa09ecba225418222dac261ca1/source/materials/src/G4NistMaterialBuilder.cc#L1656)
  • recommend that all materials in compact/materials.xml be double checked they are correct
  • also added PolyvinylAcetate and Plexiglass
• updates to compact/optical_materials.xml:
  • added several material properties tables, dumped from Fun4all standalone version (the Fun4all version will be the centralized location where we can generate these tables, for now, since the formulas are a bit too complicated to port to this repository)
• dRICh compact and source files are additions only
  • compact file: compact/drich.xml
  • source file: src/DRich.cpp

Pictures:

• dRICh geometry:

• dRICh vessel (highlighted in green) integrated in ATHENA:

• Integration dimensions:

• Scaling fun4all design to fit into ATHENA:

• Acceptance limitations (maximum eta is grey dashed line, limited by bore radius, minimum eta is red dashed line, limited by reflection of photons off the spherical mirror (to be improved!))

• Notes on spherical mirror placement