Polarization properties of X-ray tubes used for Imaging X-ray Polarimetry Explorer calibration
arXiv:2307.14814 · doi:10.1117/1.JATIS.9.3.038002
Abstract
In this work, we measured the polarization properties of the X-rays emitted from the X-ray tubes, which were used during the calibration of the instrument onboard Imaging X-ray Polarimetry Explorer (IXPE). X-ray tubes are used as a source of unpolarized X-rays to calibrate the response of the gas pixel detectors to unpolarized radiation. However, even though the characteristic fluorescent emission lines are unpolarized, continuum bremsstrahlung emission can be polarized based on the geometry of the accelerated electrons and emitted photons. Hence, characterizing the contribution of polarized X-rays from bremsstrahlung emission is of interest, also for future measurements. We find that when accelerated electrons are parallel to the emitted photons, the bremsstrahlung emission is unpolarized, and when they are perpendicular, the polarization increases with energy, as expected from the theoretical predictions. A comparison with the theoretical predictions is also shown.
30 pages, 12 Figures and 6 tables. Published in Journal of Astronomical Telescopes, Instruments, and Systems (JATIS). DOI: 10.1117/1.JATIS.9.3.038002
References in corpus (6)
- Analyzing the Data from X-ray Polarimeters with Stokes Parameters
- Design, Construction, and Test of the Gas Pixel Detectors for the IXPE Mission
- IACHEC Cross-Calibration of Chandra, NuSTAR, Swift, Suzaku, and XMM-Newton with 3C 273 and PKS 2155-304
- An algorithm to calibrate and correct the response to unpolarized radiation of the X-ray polarimeter on board IXPE
- In-flight calibration system of Imaging X-ray Polarimetry Explorer
- The IXPE Instrument Calibration Equipment