Femtolens Imaging of a Quasar Central Engine Using a Dwarf Star Telescope

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American Astronomical Society

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We show that it is possible to image the structure of a distant quasar on scales of <~ AU by constructing a telescope that uses a nearby dwarf star as its "primary lens" together with a satellite-borne "secondary." The image produced by the primary is magnified by ~10^6 in one direction but is contracted by 0.5 in the other and therefore contains highly degenerate one-dimensional information about the two-dimensional source. We discuss various methods for extracting information about the second dimension including "femtolens interferometry" where one measures the interference between different parts of the one-dimensional image with each other. Assuming that the satellite could be dispatched to a position along a star-quasar line of sight at a distance r from the Sun, the nearest available dwarf-star primary is likely to be at ~30 pc (r/45 AU^)-2. The secondary should consist of a one-dimensional array of mirrors extending ~170 m to achieve 1 AU resolution or ~350 m to achieve << 1 AU resolution.



gravitational lensing, instrumentation: interferometers, quasars:general


Andrew Gould and B. Scott Gaudi, "Femtolens Imaging of a Quasar Central Engine Using a Dwarf Star Telescope," The Astrophysical Journal 486, no. 2 (1997), doi:10.1086/304569