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This content will become publicly available on August 2, 2023

Title: Revisiting the continuum reverberation lags in the AGN PKS 0558−504
ABSTRACT We present a revised analysis of the photometric reverberation mapping campaign of the narrow-line Seyfert 1 galaxy PKS 0558 − 504 carried out with the Swift Observatory during 2008–2010. Previously, Gliozzi et al. (2013) found using the Discrete Correlation Function (DCF) method that the short-wavelength continuum variations lagged behind variations at longer wavelengths, the opposite of the trend expected for thermal reprocessing of X-rays by the accretion disc, and they interpreted their results as evidence against the reprocessing model. We carried out new DCF measurements that demonstrate that the inverted lag-wavelength relationship found by Gliozzi et al. resulted from their having interchanged the order of the driving and responding light curves when measuring the lags. To determine the inter-band lags and uncertainties more accurately, we carried out new measurements with four independent methods. These give consistent results showing time delays increasing as a function of wavelength, as expected for the disc reprocessing scenario. The slope of the re-analysed delay spectrum appears to be roughly compatible with the predicted τ ∝ λ4/3 relationship for reprocessing by an optically thick and geometrically thin accretion disc, although the data points exhibit a large scatter about the fitted power-law trend.
Authors:
; ; ; ; ; ; ;
Award ID(s):
1907290
Publication Date:
NSF-PAR ID:
10358848
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
515
Issue:
2
Page Range or eLocation-ID:
2890 to 2900
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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