Effective Area
>2000 cm2 at 1.5 keV
Field of View
5′ (non-imaging)
Energy Resolution
85 eV at 1 keV
137 eV at 6 keV
XTI consisted of aligned collection of 56 X-ray “concentrator” optics (XRC) and silicon drift detector (SDD) pairs. Each XRC collected X-rays over a large geometric area from a roughly 30 arcmin2 region of the sky and focuses them onto a small SDD. The SDD detected individual photons, recording their energies with good (few percent) spectral resolution and their detection times to 100 nanoseconds RMS relative to Universal Time. Together, this assemblage provided a high signal-to-noise-ratio photon-counting capability within the 0.2–12 keV X-ray band, perfectly matched to the typical spectra of neutron stars as well as a broad collection of other astrophysical sources.
