2008/04/21 by P. Arevalo, P. Arvalo, I. M. McHardy +1 · 2 citations
Physics and Astronomy · #Accretion (finance) #Active galactic nucleus #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Black hole (networking) #Energy (signal processing) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Lag #Light curve #Spectral density #Spectral line #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13367.x
accepted for publication in MNRAS
arxiv created 2008/04/21 · openalex publication_date 2008/06/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
To investigate further the comparison between active galactic nuclei (AGN) and black hole X-ray binaries, we have studied the main X-ray variability properties of the Seyfert 1 galaxy Mrk 335. We put particular emphasis on the X-ray time lags, which is a potentially important diagnostic of physical models. From a 100 ks observation by XMM–Newton, we show that the power spectrum of this source is well fitted by a bending power-law model, and the bend time-scale Tb is precisely at the value predicted by the Tb versus Hβ linewidth relation of McHardy et al. Variations in different energy bands show time-scale-dependent time lags, where higher energy bands lag lower ones. The lag, τ, varies as a function of the Fourier frequency, f, of the variability component in the light curves as τ∝f−1 at low frequencies, but there is a sharp cut-off in the lags at a frequency close to the bend frequency in the power spectrum. Similar behaviour is seen in black hole X-ray binary systems. The length of the time lags increases continuously with energy separation, in an almost loglinear relation. We show that the lag spectra can be produced by fluctuations propagating through the accretion flow as long as the energy spectrum of the X-ray emitting region hardens towards the centre.