Angular momentum transfer and polarization degree of ions with two-valence electrons by electron impact

We study for electron-impact excitation of ions with two valence electrons (Be2+, C2+ and Si2+) from the ground state to the first 1P0 state using the R-matrix method. The integral cross sections and polarization degree for this transition of each ion are obtained. The differential cross sections and angular momentum transfer are also shown at a few energies in the non-resonant region. The present angular momentum transfer for Be2+ and C2+ at small scattering angles has positive values, while it is negative for Si2+.