Dual mirror implementation

[chchatte92]

Briefly, what does this PR introduce?

This PR tries to implement the two mirrors of different radii to handle the spherical aberration and improve the Cherenkov angular resolution.

What kind of change does this PR introduce?

• The code implements dual mirror for the dRICH. It uses the box method to implement two mirrors. The 'Half space' method is still not working.
• The upper mirror is implemented with a smaller radius, so that the photons dive into the sensor surface.

To be addressed issues

• Many more deflected photons
• Sensor plane optimization

Please check if this PR fulfills the following:

This is a draft pull and @c-dilks is asked to review the changes

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

No

Does this PR change default behavior?

No

[chchatte92]

@c-dilks
I checked the conflicts; there are two conflicts wrt main. The first one related to the mirror description
and the second one is related to the sensor X,Y,Z and radius. Now the first one is obvious. We need to deal a bit with the second one. Maybe we can have a discussion with Marco and Luca. The spherical patch, I have however kept the same.

[chchatte92]

Here are the ring images with the current configuration;
dual mirror:

single mirror:

[chchatte92]

The photons on the sensor surface:

[chchatte92]

The photons hits not very clean (5 tracks in 24 phi bins and 3 eta bins)
dual mirror:

Chris' PR:

To be addressed

[chchatte92]

The validation method is adopted as the following

• To use single mirror configuration each time with one of the two mirrors' parameters.
• Extract the resolution using single particles at a fixed eta and uniform phi.

[rahmans1]

@chchatte92 What's the status of this PR? Does this need to be merged for the February simulation campaign?