Full polarization measurement of synchrotron radiation with use of soft x‐ray multilayers

Using two Ru/Si multilayers as a phase shifter and an analyzer, we have measured the state of polarization for 12.8‐nm synchrotron radiation (SR) of the beam line 11A at the Photon Factory. It has been found that the state of polarization depends largely on the vertical inclination angle of the first mirror of the beam line. From the phase information, we have determined parameters of the polarization ellipse including handedness.