OJ 287: Wavelet Analysis of the 3-Year Light Curve

  • Harry J. Lehto
Conference paper
Part of the Astrophysics and Space Science Library book series (ASSL, volume 218)


OJ 287 is a highly variable blazar. Sillanpää et al (1988) detected a ~12 year cyclicity in the optical light curve, and predicted that an outburst will occur in 1994. The international project OJ-94, consisting now of about 50 observers in 12 countries was launched in 1993 to monitor teh source. The collaboration has obtained e.g. a V-band light curve with over 3000 points, yielding the best coverage for any blazar. After the outburst took place close to the expected time, Lehto and Valtonen (1996) succesfully predicted a second outburst for November 1995. Further modelling (Sundelius et al 1996) predicted a third outburst, which was expected to be slower and occur soon after the second outburst. This also took place. The aim of this paper is to quantify the type of variability seen in OJ 287 during three years of the project.


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Copyright information

© Springer Science+Business Media Dordrecht 1997

Authors and Affiliations

  • Harry J. Lehto
    • 1
  1. 1.Tuorla ObservatoryTurku UniversityPiikkiöFinland

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