Abstract
The bright BL Lac object PKS 2155-304 was observed with EXOSAT 9 times between 1983 and 1985 for a total of 80 hours. During some observations the source appeared stable, while during others, flare-like activity was observed, the intensity doubling in less than an hour. Here we present a power spectrum analysis of the 3 brightest observations. Significant power is found between ≈- 5 x 10−5 and ≈- 2 x 10−3 Hz. Power spectra obtained from the 1–7 keV light curves, using standard Fourier techniques, have an average power-law slope of ≈- -1.5. We find evidence that the power spectrum is affected by low-frequency “leakage”.
On leave from I.C.R.A., Dipartimento di Fisica'G.Marconi', Universita' di Roma, I.
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© 1989 Springer-Verlag
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Tagliaferri, G., Stella, L., Maraschi, L., Treves, A., Morini, M. (1989). The X-ray variability of PKS 2155-304: A power spectrum analysis. In: Maraschi, L., Maccacaro, T., Ulrich, M.H. (eds) BL Lac Objects. Lecture Notes in Physics, vol 334. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0031177
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DOI: https://doi.org/10.1007/BFb0031177
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