Letter | Published:

Laboratory detection of X-ray fringes with a grazing-incidence interferometer

Nature volume 407, pages 160162 (14 September 2000) | Download Citation



Starting with Galileo's observations of the Solar System, improvements of an order of magnitude in either the sensitivity or resolution of astronomical instruments have always brought revolutionary discoveries. The X-ray band of the spectrum, where exotic objects can have extremely high surface brightness1, is ideally suited for significant improvements in imaging, but progress has been impeded by a lack of optics of sufficiently high sensitivity and quality. Here we present an X-ray interferometer design that is practical for adaptation to astronomical observatories. Our prototype interferometer, having just under one millimetre of baseline, creates fringes at 1.25 keV with an angular resolution of 100 milliarcseconds. With a larger version in orbit it will be possible to resolve X-ray sources at 10-7 arcseconds, three orders of magnitude better than the finest-resolution images ever achieved on the sky (in the radio part of the spectrum) and over one million times better than the current best X-ray images. With such resolutions, we can study the environments of pulsars, resolve and then model relativistic blast waves, image material falling into a black hole, watch the physical formation of astrophysical jets, and study the dynamos of stellar coronae.

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We thank N. White, D. Windt, J. Bixler, K. Doty, J. Carter, K. Herren, D. Goodman, J. Kolodziejczak, G. Zirnstein, T. Kester, M. Weisskopf and M. Karovska. This work was funded by NASA with additional technical support from the NASA Goddard Space Flight Center.

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  1. *University of Colorado, Boulder, Colorado 80309-0389, USA

    • Webster Cash
    • , Ann Shipley
    •  & Steve Osterman
  2. †NASA/Marshall Space Flight Center , Huntsville, Alabama 35812, USA

    • Marshall Joy


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Correspondence to Webster Cash.

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