The Q0957+561 Time Delay, Quasar Structure, and Microlensing

  • R. E. Schild
  • D. J. Thomson
Part of the Astrophysics and Space Science Library book series (ASSL, volume 218)


Determination of the Q0957+561 A,B time delay from long-term brightness monitoring of the random pattern of quasar fluctuations at optical and radio wavelengths constitutes the best proof that the object is indeed a gravitational lens, because microlensing and other subtle effects cause the spectra, colors and other instantaneous properties of the multiple images of a lensed quasar to be not strictly identical. Observation of a random pattern of brightness fluctuations at optical and radio frequencies has been undertaken since the source’s identification in 1979. The resulting time series of source brightness now provides fertile ground for exploration of other quasar and microlensing properties.


Gravitational Wave Light Curve Wavelet Decomposition Gravitational Lens Astrophysical Journal 
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Copyright information

© Springer Science+Business Media Dordrecht 1997

Authors and Affiliations

  • R. E. Schild
    • 1
  • D. J. Thomson
    • 2
  1. 1.Harvard-Smithsonian Center for AstrophysicsCambridgeUSA
  2. 2.Bell LaboratoriesLucent TechnologiesMurray HillUSA

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