X-ray baffle of the XMM telescope: development and results

Abstract

The high throughput X-ray spectroscopy mission XMM is the second cornerstone project in the European Space Agency (ESA) long-term program for space science. This observatory has at its heart three large X-ray telescopes, which will provide a large collecting area (1450 cm each at 1.5 keV and 600 cm2 each at 8.0 keV) with a spatial resolution around 15 arcesec. Five Flight models (including the two spare ones) of the XMM X-ray telescope have been delivered to ESA in 1998. They show optical performance. which is far better than the specifications, especially in terms of optical and X-ray stray light reduction. The low level of X-ray stray light will be an important benefit for the observation of the extended faint sources such as super nova . remnants or clusters of active galaxies. This reduction of X-ray stray light is due, in particular. to the implementation of a very complex and accurate X-ray baffle mounted at the entrance of the telescope.In this paper, we present first the need, the design. the , manufacturing and the integration of the X-ray baffle. Then, we concentrate on the verification of the performance of the baffle at ; the Centre Spatial de Liege. Finally, we will present the excellent results obtained with these baffles.1.

Simbol-X: x-ray baffle for stray-light reduction

“…For the latter, the simulation was performed without the implementation of the pre-collimator X-ray baffle. 14,15 The stray-light contamination increases with the detector radius. However, this increase is particularly severe in Simbol-X up to a factor 2 at the edge of the FoV.…”

<title>Imaging performance of the XMM-Newton x-ray telescopes</title>

“…The plates are mounted co-axial to and co-aligned with the front aperture cross section of the 58 mirror shells. The off-set of the two sieve plates from the front of the mirror system is 385 mm and 439 mm, respectively 8 . The efficiency of the sieve plate system has been ray traced and demonstrated to reduce the straylight level by a factor of 5 to 10 depending on the position in the focal plane.…”

Observational artifacts of Nuclear Spectroscopic Telescope Array: ghost rays and stray light

“…A similar design was used for XMM-Newton and with it they are able to reduce about 80% of the GR flux. 16 When the shell spacing is larger, as it is for Chandra, the baffling can be done within the optics. 17,18 To reduce the SL and background, NuSTAR designed a deployable optical shield, which would have increased the angular extent of the optical bench; although built, it was never mounted due to prelaunch scheduling constraints.…”