A new method of x-ray polarimetry based on the photoeffect in a finely segmented silicon charge coupled device (CCD) first proposed by G. W. Fraser has been confirmed using monochromatic synchrotron radiation and planar channeling radiation. For the smallest pixel dimensions (6.8 multiplied by 6.8 micrometer squared) available today in commercial optical CCD cameras an analyzing power for linear polarization in the order of 10% has been measured at energies above 10 keV. The strong energy dependence of the analyzing power has been measured in the energy range from 9 - 100 keV and is compared to expectations from detailed MC simulations. In addition to events due to photoeffect in the thin depleted front layer of the CCD also diffusion spread events resulting from much more abundant conversions deeper inside the chip were found to be very useful for simultaneous measurements of polarization, energy and position with sub-pixel accuracy (0.9 micrometer rms at 15 keV). For the first time we have now made use of the CCD polarimeter for the measurement of the linear polarization of parametric x-rays (PXR), i.e. radiation which is coherently generated by charged particles traversing a crystal.
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