Improved electron beam pipe modelling

[nat93]

Briefly, what does this PR introduce?

It contains the improved geometry of the central and far-backward beam pipes. In addition, some overlaps between ePIC and the new beam pipe are fixed by changing the detector components' inner radius (this has to be approved by detector experts).

What kind of change does this PR introduce?

• [x] Bug fix (issue #__)
• [ ] New feature (issue #__)
• [ ] Documentation update
• [ ] Other: __

Please check if this PR fulfills the following:

• [x] Tests for the changes have been added (could be checked by plotting the entire geometry, e.g., through 'dd_web_display,' or material scan, e.g., through 'g4MaterialScan_to_csv')
• [x] Documentation has been added/updated (comments were added)
• [x] Changes have been communicated to collaborators (partially, the Vacuum and Background groups approved the changes)

Does this PR introduce breaking changes? What changes might users need to make to their code?

We must check how the modified subsystem geometries affect detector performance (angular acceptance, resolution, etc.).

Does this PR change default behavior?

Yes. Now, we should have a more accurate beam pipe with an enlarged inner radius of subsystems in the forward direction to fit the new beam pipe. This may affect detector background rates.

Things to be done

Still, the materials of the beam pipes (by default, aluminum) are wrong, except for the IP beam pipe. The next step would be to fix this issue (it should be stainless steel with a copper coating).

References

Machine lattice file v6.2: esr-ring-norad.tfs and esr-survey-doug.tfs Electron beam pipe vacuum geometry (from the EIC vacuum group): detector_chamber_211004.pdf and STL file Detector geometry file - Apr 2024: EPIC Envelope - 04-03-2024.pdf Updated detector geometry table - Apr 2024: Detector-20240426

[wdconinc]

Formatted, merged main, conflicts resolved in favor of feature branch.