Wavelet analysis of AGN X-ray time series: A QPO in 3C 273?

作者：Espaillat C^*; Bregman J; Hughes P; Lloyd Davies E

来源：Astrophysical Journal, 2008, 679(1): 182-193.

DOI：10.1086/587023

• galaxies : active
• galaxies : individual (3C 273)
• X-rays : galaxies

Quasi-periodic signals have yielded important constraints on the masses of black holes in galactic X-ray binaries, and here we extend this to active galactic nuclei (AGNs). We employ a wavelet technique to analyze 19 observations of 10 AGNs obtained with the XMM-Newton EPIC pn camera. We report the detection of a candidate 3.3 ks quasi period in 3C 273. If this period represents an orbital timescale originating near a last stable orbit of 3R(s), it implies a central black hole mass of 7.3 x 10(6) M-circle dot. For a maximally rotating black hole with a last stable orbit of 0.6R(s), a central black hole mass of 8.1 x 10(7) M-circle dot is implied. Both of these estimates are substantially lower than previous reverberationmapping results, which place the central black hole mass of 3C 273 at about 2.35 x 10(8) M-circle dot. Assuming that this reverberation mass is correct, the X-ray quasi period would be caused by a higher order oscillatory mode of the accretion disk.

• 出版日期2008-5-20