Windhorst, Rogier A., Cameron, R.A., Brissenden, R.J., Elvis, M.S., Fabbiano, G., Gorenstein, P., Reid, P.B., Schwartz, D.A., Bautz, M.W., Figueroa-Feliciano, E., Petre, R., White, N.E., and Zhang, W.W.
Abstract: The new cosmological frontier will be the study of the very first stars, galaxies and black holes in the early Universe. These objects are invisible to the current generation of X-ray telescopes, such as Chandra. In response, the Generation-X (“Gen-X”) Vision Mission has been proposed as a future X-ray observatory which will be capable of detecting the earliest objects. X-ray imaging and spectroscopy of such faint objects demands a large collecting area and high angular resolution. The Gen-X mission plans 100m2 collecting area at 1keV (1000× that of Chandra), and with an angular resolution of 0.1″. The Gen-X mission will operate at Sun–Earth L2, and might involve four 8m diameter telescopes or even a single 20m diameter telescope. To achieve the required effective area with reasonable mass, very lightweight grazing incidence X-ray optics must be developed, having an areal density 100× lower than in Chandra, with mirrors as thin as 0.1mm requiring active on-orbit figure control. The suite of available detectors for Gen-X should include a large-area high resolution imager, a cryogenic imaging spectrometer, and a grating spectrometer. We discuss use of Gen-X to observe the birth of the first black holes, stars and galaxies, and trace their cosmic evolution. [Copyright &y& Elsevier]