Superluminal Gravitational Microlensing Events in PKS 0537-441 and Prospects for Future Detection

  • G. C. Surpi
  • G. E. Romero
  • H. Vucetich
Conference paper
Part of the International Astronomical Union / Union Astronomique Internationale book series (IAUS, volume 173)


The BL-Lac object PKS 0537-441 has recently displayed strong intraday variability at 1.42 GHz on time scales of ∼ 104 s. Such kind of variability is hardly consistent with an intrinsic-to-source origin, since apparent brightness temperatures higher than 1021 K are implied for the emitting region in the source.

An alternative explanation for this ultra-rapid radio variability in PKS 0537-441 is developed based on gravitational microlensing of a superluminal component in the blazar caused by compact objects in the halo of an intervening galaxy. The mass of the microlenses is estimated and the blazar is proposed as a good candidate in a systematic search for extragalactic MACHOs.


Dark Matter Rotation Curve Compact Object Dark Matter Density Dark Halo 
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Copyright information

© International Astronomical Union 1996

Authors and Affiliations

  • G. C. Surpi
    • 1
  • G. E. Romero
    • 2
  • H. Vucetich
    • 3
  1. 1.Depto. de Física, FCEyNUniversidad de Buenos Aires Ciudad Univresistaria - Pab. IBs. AsArgentina
  2. 2.Instituto Argentino de Radioastronomía CC5Bs. AsArgentina
  3. 3.FCAyG - Universidad Nacional de La PlataBs. AsArgentina

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