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We measured the X-ray polarization using our micro-pixel chamber with a strip readout, while changing the X-ray energy (5– 18 keV ) and gas mixtures (neon- and argon-based). As a result, modulation factors of 0.18 (at 9 keV ) and 0.12 (at 14 keV ) were obtained for neon- and argon-based mixtures, respectively. We also simulated this experiment utilizing a Monte-Carlo code, EGS4, which reproduced the experimental results quite well. According to the Monte-Carlo simulation, the modulation factor should be improved by a pixel-readout detector. The simulated modulation factors are 0.25 (for X-ray with energy at >6 keV ) with a neon-based gas mixture and 0.18 (for X-ray at >10 keV ) with an argon-based one.

Measurements of the linear polarisation dependence of the X-ray photocurrent from gold were made at the Daresbury Synchrotron Radiation Source using a novel rotating chamber and the tuneable linear polarisation of the undulator beamline 5U.1. The overall energy range was 65–1000 eV. At a grazing angle of 8°, significant polarisation sensitivity was observed (modulation factor 0.02 M

X-ray polarimetry with CCD has been performed using a polarized X-ray beam from an electron impact X-ray source. The standard data reduction method employing double-pixel events yields the modulation factor M of 0.14 at 27 keV and 0.24 at 43 keV for the 12 lm pixel size CCD chip. We develop a new data reduction method, in which multi-pixel events are employed, and which approximates the charge spread as an oval shape. We optimize the reduction parameters, so that we improve the P .*/ (minimum detectable polarization degree) by factor of three from the value obtained through the usual double-pixel event method. ( 1999 Elsevier Science B.V. All rights reserved.