Optical layout of the TERAS BL-5B beamline and a schematic of the calibration factor measurement system. PM1, PM2: photomultipliers; A1, A2: amplifiers; LPF1, LPF2: electrical low-pass filters (cutoff frequency ); V1–3: digital voltmeters; LIA1, LIA2: digital lock-in amplifiers operated in the and modes, respectively; DCCT: dc current transformer; and and monitors: detectors for the light incident and transmitted through the polarimeter, respectively.
Typical data set of (a) and (b) observed by the conventional method of polarization analysis as a function of the relative phase retardation of the undulator magnets at wavelengths (black square) and 220 nm (red circle) with electron energy . The solid curve shows the results of the least-squares fitting for the observed dependences using Eq. (7).
Typical data set for the transmitted light intensity, (a), , (b), , and (c), , as a function of the rotation angle of QR2, , at the rotation angle of QR1, (black square), (red circle), (green up triangle), and (blue down triangle) with wavelength and electron energy . The solid curve shows the results of the least-squares fitting for the observed dependences using Eq. (14).
Absolute values of the calibration factors, (closed black square) and (open red circle), obtained by the proposed method and expressed as a function of the wavelength and undulator spectrum with electron energy .
Variation in the value of at a wavelength with respect to the storage-ring current (closed black circle). The values are normalized by the maximum ring current of 160 mA. The red line is a visual reference.
(a) vuv-CD spectra of a -ACS aqueous solution at calibrated using the values obtained by the proposed method (closed black circle) and the conventional method (open red circle), and the standard spectra, measured using a conventional CD spectrophotometer (green curve). (b) The vuv-LD spectra of a -tilted single silica plate calibrated using the values obtained by the proposed (closed black circle) and the conventional method (open red circle), and the theoretical standard spectra (green curve).
Calculated trajectory of the electron in our undulator at at (black line), (green line), (red line), (blue line), and (purple line). VLP, HLP, RCP, and LCP denote the vertical and horizontal linear polarizations and right and left circular polarizations, respectively.
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