ANGULAR-DISTRIBUTION MEASUREMENT OF VARIOUS L3 X-RAY TRANSITIONS

The presence of the magnetic quadrupole term in addition to the electric dipole one in the multipole expansion of the radiation field is reflected in the angular distribution of the x-ray transition. To extend the previous works we studied the angular distribution of different L3 x-ray lines of Ba, Sm and Er experimentally for proton impact at 0.23, 0.28 and 0.35 MeV bombarding energies respectively, using a Si(Li) detector. The anisotropy parameter ratios of the Ll and L-alpha transitions were found to be 5.2 +/- 2.8, 5.5 +/- 0.7 and 6.9 +/- 1.5. Angular distributions of Tb L-shell x-rays were also measured by a high resolution crystal spectrometer for 0.556 MeV amu-1 nitrogen ions, a value of 3.5 +/- 2.5 was obtained for the anisotropy parameter ratio. These ratios deviate significantly from the theoretical ones. The obtained ratios were in good accord with the same quantities derived from the earlier K-alpha-1-L angular correlation parameters. The effect of the magnetic quadrupole mixing on the determination of the alignment parameter is demonstrated for the case of the L3 subshell of gold.