Can He, He+, or He+2 absorb a visible photon? If yes, which ones?

Question

Can He, He+, or He+2 absorb a visible photon? If yes, which ones?

Answer 1

He and He+ can absorb a photon, excitating their electrons.

since He2+ doesn't have any electrons, it doesn't absorb photons in casual way (such as electron excitation in spectra).

But some sort of other interaction can be seen - if the photon has enough energy, electron-positron pair can be created by the interaction, but this is not normal absorbtion.