A Partial Eclipse of the Heart: The Absorbed X-ray Low State in Mrk 1048

Abstract

We present two new XMM-Newton observations of an unprecedented low flux state in the Seyfert 1 Mrk 1048 (NGC 985), taken in 2013. The X-ray flux below 1 keV drops by a factor of 4-5, whereas the spectrum above 5 keV is essentially unchanged. This points towards an absorption origin for the low state, and we confirm this with spectral fitting, finding that the spectral differences can be well modelled by the addition of a partial covering neutral absorber, with a column density of $\sim 3\times 10^{22}$~cm${}^{-2}$ and a covering fraction of $\sim 0.6$. The optical and UV fluxes are not affected, and indeed are marginally brighter in the more recent observations, suggesting that only the inner regions of the disk are affected by the absorption event. This indicates either that the absorption is due to a cloud passing over the inner disk, obscuring the X-ray source but leaving the outer disk untouched, or that the absorber is dust-free so the UV continuum is unaffected. We use arguments based on the duration of the event and the physical properties of the absorber to constrain its size and location, and conclude that it is most likely a small cloud at $\sim 10^{18}$cm from the source.

Accepted to MNRAS

References in corpus (10)

• Piecing Together the X-ray Background: Bolometric Corrections for Active Galactic Nuclei
• Occultation measurement of the size of the X-ray emitting region in the Active Galactic Nucleus of NGC 1365
• Paper II: Calibration of the Swift ultraviolet/optical telescope
• A fast and long-lived outflow from the supermassive black hole in NGC 5548
• On why the Iron K-shell absorption in AGN is not a signature of the local Warm/Hot Intergalactic Medium
• The First Swift Ultra-Violet/Optical Telescope GRB Afterglow Catalog
• The Origin of the Intrinsic Scatter in the Relation Between Black Hole Mass and Bulge Luminosity for Nearby Active Galaxies
• Discovery of the Narrow-Line Seyfert 1 galaxy Mkn 335 in an historical low X-ray flux state
• XMM-Newton View of the Multi-Phase Warm Absorber in Seyfert 1 Galaxy NGC985
• XMM-Newton observation of the deep minimum state of PG 2112+059: A spectrum dominated by reflection from the accretion disk?

Cited by in corpus (6)

• The eROSITA Final Equatorial Depth Survey (eFEDS): Complex absorption and soft excesses in hard X-ray--selected active galactic nuclei
• Optical and X-ray discovery of the changing-look AGN IRAS23226-3843 showing extremely broad and double-peaked Balmer profiles
• Multi-epoch properties of the warm absorber in the Seyfert 1 galaxy NGC 985
• Comparing Reflection and Absorption Models for the Soft X-ray Variability in the NLS1 AGN UGC 11763
• X-ray Unveiling Events in a z~1.6 Active Galactic Nucleus in the 7 Ms Chandra Deep Field-South
• Swift, NuStar and XMM-Newton observations of the NLS1 galaxy RX J2317.8-4422 in an extreme X-ray low flux state