Selection rules for multiphoton vs single-photon ionization

[phys-student-9]

Question: For ionization of a homonuclear diatomic, how do the selection rules differ for a nonresonant 2-photon ionization process and a 1-photon ionization process?

 

[phys-student-9]

Specifically, I am wondering about the angular momentum selection rules. For a 1-photon ionization, since the photon has 1 quantum of angular momentum, I think the change in the total orbital angular momentum of the molecule would have to be +/- 1. And for a 2-photon ionization, which I'm trying to do non-resonantly, it would be +/- 2.
The gerade/ungerade selection rules should not matter since these are being ionized.
Does this seem reasonable?

 

[DrClaude]

Sounds right.