1 July 1990 Bragg crystal polarimeters
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Optical Engineering, 29(7), (1990). doi:10.1117/12.55661
A Bragg crystal oriented at 45° to an incoming beam of x rays acts as a polarization analyzer. This crystal geometry preferentially reflects those x rays that satisfy the Bragg condition and whose electric vectors are perpendicular to the plane defined by the incident and reflected photons. X rays with electric vectors parallel to this plane of incidence are photoelectrical^ absorbed. The energy bandwidth of nearly perfect crystals is extremely small, which makes them very inefficient x-ray polarimeters. This limitation is particularly acute for observations of the relatively weak x-ray continuum of stellar sources. The bandwidth can be greatly increased by employing mosaic or ideally imperfect crystals. Mosaic crystals possess a high integrated reflectivity, which results in a large increase in the reflection of continuum radiation. A review of the theory and performance characteristics of crystal polarimeters designed for observations of cosmic x-ray sources is presented.
Eric H. Silver, Jeff Holley, Klaus Ziock, Robert Novick, Philip E. Kaaret, Martin C. Weisskopf, Ronald F. Elsner, Jeffrey W. Beeman, "Bragg crystal polarimeters," Optical Engineering 29(7), (1 July 1990). http://dx.doi.org/10.1117/12.55661



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