The Imaging X-ray Polarimetry Explorer 2.5 years later

Abstract

<p>We have, at last, an observatory dedicated to X-ray polarimetry that has been operational since December 9<sup/>, 2021. The Imaging X-ray Polarimetry Explorer (IXPE) is a NASA SMEX mission, in partnership with ASI, based on three X-ray telescopes, each equipped with a polarization-sensitive detector in the focus. An extending boom was deployed in orbit, positioning the detectors at the optimal distance from the optics, which have a 4-meter focal length. The spacecraft is three-axis stabilized, providing power, attitude determination and control, transmission, and commanding capabilities. After two and a half years of observation, IXPE has detected positive polarization from nearly all classes of celestial sources that emit X-rays. In this report, we describe the IXPE mission, detailing the performance of the scientific instrumentation after 2.5 years of operation. We also present the main astrophysical results and a few examples of scientific performance during flight.</p>