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arXiv · 1610.06677

Performance of the PRAXyS X-ray Polarimeter

W. B. Iwakiri·J. K. Black·R. Cole·T. Enoto·A. Hayato·J. E. Hill·K. Jahoda·P. Kaaret·T. Kitaguchi·M. Kubota·H. Marlowe·R. McCurdy·Y. Takeuchi·T. Tamagawa
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Abstract

The performance of the Time Projection Chamber (TPC) polarimeter for the Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS) Small Explorer was evaluated using polarized and unpolarized X-ray sources. The PRAXyS mission will enable exploration of the universe through X-ray polarimetry in the 2-10 keV energy band. We carried out performance tests of the polarimeter at the Brookhaven National Laboratory, National Synchrotron Light Source (BNL-NSLS) and at NASA's Goddard Space Flight Center. The polarimeter was tested with linearly polarized, monochromatic X-rays at 11 different energies between 2.5 and 8.0 keV. At maximum sensitivity, the measured modulation factors at 2.7, 4.5 and 8.0 keV are 27%, 43% and 59%, respectively and the measured angle of polarization is consistent with the expected value at all energies. Measurements with a broadband, unpolarized X-ray source placed a limit of less than 1% on false polarization in the PRAXyS polarimeter.

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W. B. Iwakiri, J. K. Black, R. Cole, T. Enoto, A. Hayato, J. E. Hill, K. Jahoda, P. Kaaret, T. Kitaguchi, M. Kubota, H. Marlowe, R. McCurdy, Y. Takeuchi, T. Tamagawa. 2016-10-21. Performance of the PRAXyS X-ray Polarimeter. https://doi.org/10.1016/j.nima.2016.09.024

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