Multiphoton ionization of cesium via quadrupole transitions: Photoelectron angular distributions and polarization effects on total ionization rates

We report measurements of photoelectron angular distributions via electric quadrupole transitions in cesium atoms using multiphoton excitation techniques. Experimental results are presented for the cases of one-photon resonant, two-photon ionization via the 6d ${\mathrm{}}^{2}$${D}_{3/2}$ and 6d ${\mathrm{}}^{2}$${D}_{5/2}$ electric quadrupole transitions and for one-photon resonant, three-photon ionization via the 5d ${\mathrm{}}^{2}$ ${\mathrm{D}}_{3/2}$ and 5d ${\mathrm{}}^{2}$${D}_{5/2}$ transitions. The ratios of the total ionization rates for linearly and circularly polarized light have also been measured for the 6d ${\mathrm{}}^{2}$${\mathrm{D}}_{3/2}$ and 6d ${\mathrm{}}^{2}$${D}_{5/2}$ states. A theoretical analysis and detailed comparison with the experimental results are given.