Fig. 3: The state-to-state transition probabilities for collision between Ar+(2P3/2,1/2) and N2.

a The calculated state-to-state transition probabilities for the collisional energy transfer processes of Ar+(2P3/2) + N2 → Ar+(2P3/2) + N2(v′) (red) and Ar+(2P3/2) + N2 → Ar+(2P1/2) + N2(v′) (black) at the COM collision energy of 1.58 eV; (b) the calculated state-to-state transition probabilities for the collisional energy transfer processes of Ar+(2P1/2) + N2 → Ar+(2P1/2) + N2(v′) (red) and Ar+(2P1/2) + N2 → Ar+(2P3/2) + N2(v′) (black) at the COM collision energy of 1.58 eV; (c, d) presents the transition probabilities for the same processes as those in (a, b), respectively, but only signals in the backward hemispheres (scattering angle >90°) are counted.