Optimize the computation by using photon energy instead of wavelength.

[burmist-git]

Optimize the computation by using photon energy instead of wavelength.
This is related to the fact that Cherenkov light has a photon energy distribution that is flat with respect to wavelength (~1/lambda^2).

[maxnoe]

This is not purely an optimization, it will change the result from being a percentage efficiency to a bandwidth in Cherenkov photon energy.

So I'd call this "Compute Energy Bandwidth in Muon Analysis".

I would also propose to add this as a separate class for now, to be able to compare the efficiency estimator and the bandwidth estimator.