Status of ART-XC/SRG instrument

Abstract

Spectrum Roentgen Gamma (SRG) is an X-ray astrophysical observatory, developed by Russia in collaboration with Germany. The mission will be launched in March 2016 from Baikonur, by a Zenit rocket with a Fregat booster and placed in a 6-month-period halo orbit around L2. The scientific payload consists of two independent telescopesa softx-ray survey instrument, eROSITA, being provided by Germany and a medium-x-ray-energy survey instrument ART-XC being developed by Russia. ART-XC will consist of seven independent, but co-aligned, telescope modules. The NASA Marshall Space Flight Center (MSFC) is fabricating the flight mirror modules for the ART-XC/SRG. Each mirror module will be aligned with a focal plane CdTe double-sided strip detectors which will operate over the energy range of 630 keV, with an angular resolution of <1′, a field of view of ~34′ and the an expected energy resolution of about 10% at 14 keV.

Calibration of the ART-XC mirror modules at MSFC

“…The ART-XC field of view (FOV) is 36 arcmin in diameter, which is mainly determined by the working area of the CdTe focal plane detectors (28.56 × 28.56 mm, [2]). According to a raytrace simulation model of the ART-XC mirror optics, the effective-area drop (vignetting) at the FOV edge is about 20% at 8 keV (Tkachenko et al, in preparation).…”

“…Studing the radial profiles of the on-axis PSF for the different mirror modules, we found that the systematic deviation between the modules can reach 20 − 30%. The angular size of the ART-XC detector element of ∼45 arcsec is a factor of 1.5 larger than the ∼ 30 arcsec halfpower diameter (HPD, corresponding to half of the focused X-rays) of the optics [2], which allows us to supress detailed structures of the PSF for simplicity, by averaging them azimuthally at a given off-axis angle.…”

“…The Spectrum-Röntgen-Gamma (SRG) mission is a Russian-German X-ray astrophysical observatory that carries two co-aligned X-ray telescope systems, the Germanled extended ROentgen Survey with an Imaging Telescope Array (eROSITA, [1]) and the Russian-led Astronomical Röntgen Telescope X-ray Concentrator (ART-XC, [2]). Both telescope systems consist of 7 independent mirror modules and focal plane detectors, operating in 0.2 − 10 keV (eROSITA) and 5 − 30 keV (ART-XC).…”