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• A change in the variability properties of the intraday variable quasar 0917+624 ,
  A. Kraus, A. Witzel, T.P. Krichbaum, A.P. Lobanov, B. Peng, & E. Ros,
  Astronomy & Astrophysics, 352, L107-L110 (1999)
  
  • Abstract We observed the quasar 0917+624 three times at a wavelength of 6cm in order to study its short-timescale variability. In December 1997 and February 1999, the source showed its usual characteristics: variations on a 10-15% level habe vound on timescales ≤1.5 days. In contrast, in September 1998 the source exhibited a monotonic increase of about 7% during a five-day-observing campaign. This corresponds to a change in brightness temperature of two orders of magnitude. We discuss shortly several mechanisms which may cause the observed change of the variability properties of 0917+624.

Eduardo Ros ros@mpifr-bonn.mpg.de

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