A SOFT X-RAY REVERBERATION LAG IN THE AGN ESO 113-G010

Journal Article · Sun Feb 10 04:00:00 EST 2013 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/764/1/L9· OSTI ID:22130918

Cackett, E. M. ^[1]; Fabian, A. C.; Kara, E. ^[2]; Zogbhi, A.; Reynolds, C. ^[3]

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1. Department of Physics and Astronomy, Wayne State University, 666 W. Hancock St, Detroit, MI 48201 (United States)
2. Institute of Astronomy, University of Cambridge, Madingley Rd, Cambridge, CB3 0HA (United Kingdom)
3. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)

Reverberation lags have recently been discovered in a handful of nearby, variable active galactic nuclei (AGNs). Here, we analyze a {approx}100 ks archival XMM-Newton observation of the highly variable AGN, ESO 113-G010, in order to search for lags between hard, 1.5-4.5 keV, and soft, 0.3-0.9 keV, energy X-ray bands. At the lowest frequencies available in the light curve ({approx}< 1.5 Multiplication-Sign 10{sup -4} Hz), we find hard lags where the power-law-dominated hard band lags the soft band (where the reflection fraction is high). However, at higher frequencies in the range (2-3) Multiplication-Sign 10{sup -4} Hz we find a soft lag of -325 {+-} 89 s. The general evolution from hard to soft lags as the frequency increases is similar to other AGNs where soft lags have been detected. We interpret this soft lag as due to reverberation from the accretion disk, with the reflection component responding to variability from the X-ray corona. For a black hole mass of 7 Multiplication-Sign 10{sup 6} M{sub Sun} this corresponds to a light-crossing time of {approx}9 R{sub g} /c; however, dilution effects mean that the intrinsic lag is likely longer than this. Based on recent black hole mass scaling for lag properties, the lag amplitude and frequency are more consistent with a black hole a few times more massive than the best estimates, though flux-dependent effects could easily add scatter this large.

• OSTI ID: 22130918
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 764; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
AMPLITUDES
BLACK HOLES
EVOLUTION
GALAXY NUCLEI
KEV RANGE 01-10
MASS
REFLECTION
SCALING
SOFT X RADIATION
X-RAY GALAXIES