Optimization of polarimetry sensitivity for X-ray CCD

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 em ploying double-pixel events yields the modulation factor M of 0.14 at 27 ke V and 0.24 at 43 keV for the 12 mu m 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-min (minimum detectable polarization d egree) by factor of three from the value obtained through the usual double- pixel event method. (C) 1999 Elsevier Science B.V. All rights reserved.