The Microchannel X-ray Telescope (MXT) is one of four instruments on the Space-based multi-band astronomical Variable Objects Monitor (SVOM) satellite mission, launched on the 22nd June 2024. The MXT is a narrow-field-optimised, lobster eye X-ray focusing telescope, consisting of an array of 25 square MPOs, with a focal length of 1.14 m and working in the energy band 0.2 - 10 keV. The design of the MXT optic (MOP) is optimised to give a 1 degree FoV to match the detector size, but the optic has the unique characteristics of a lobster eye design, with a wide FoV of 6 degree diameter, and a PSF, which is constant over the entire FoV. The MPOs on the Flight Module (FM) MOP have a pore size of 40 um giving the optimum thicknesses across the aperture of 2.4 mm in the centre and 1.2 mm at the edges. Using specific target sources, the in-orbit calibration of the optic is here described, and compared to the extensive on-ground calibration, which was carried out at the PANTER test facility, MPE, Germany. The design and limitations of the electron diverter, situated directly behind the optic, are also discussed.
@article{arxiv.2605.10263,
title = {Design and in-orbit calibration of the MXT optics},
author = {Charly Feldman and James Pearson and Gillian Butcher and Richard Willingale and Paul O'Brien and Julian Osborne and Karine Mercier and Jean-Michel Le Duigou and Diego Gotz},
journal= {arXiv preprint arXiv:2605.10263},
year = {2026}
}
Comments
Accepted for publication in the SVOM special issue in Research in Astronomy and Astrophysics: 7 pages, 10 figures, 1 table