Astronomy and Astrophysics | VOL. 397
Read

1ES 1927+654: Persistent and rapid X-ray variability in an AGN with low intrinsic neutral X-ray absorption and narrow optical emission lines

Publication Date Jan 1, 2003

Abstract

We present X-ray and optical observations of the X-ray bright AGN I ES 1927+654. The X-ray observations obtained with ROSAT and Chandra reveal persistent, rapid and large scale variations, as well as steep 0.1-2.4 keV (Γ = 2.6 ′ 0.3) and 0.3-7.0 keV (F = 2.7 ′ 0.2) spectra. The measured intrinsic neutral X-ray column density is approximately 7 x 10 2 0 cm - 2 . The X-ray timing properties indicate that the strong variations originate from a region, a few hundred light seconds from the central black hole, typical for type 1 AGN. High quality optical spectroscopy reveals a typical Seyfert 2 spectrum with some host galaxy contamination and no evidence of Fe II multiplets or broad hydrogen Balmer wings. The intrinsic optical extinction derived from the BLR and NLR are A v > 3.7 and A v = 1.7, respectively. The X-ray observations give an A v value of less than 0.58, in contrast to the optical extinction values. We discuss several ideas to explain this apparent difference in classification including partial covering, an underluminous BLR or a high dust to gas ratio.

Concepts
Powered ByUnsilo

X-ray Observations
Narrow Optical Emission Lines
Host Galaxy Contamination
Rapid X-ray Variability
Intrinsic X-ray
Large Scale Variations
Optical Extinction
Light Seconds
Black Hole
Intrinsic X-ray Absorption

Introducing Weekly Round-ups!Beta

Powered by R DiscoveryR Discovery

Round-ups are the summaries of handpicked papers around trending topics published every week. These would enable you to scan through a collection of papers and decide if the paper is relevant to you before actually investing time into reading it.

Climate change Research Articles published between Jun 20, 2022 to Jun 26, 2022

R DiscoveryJun 27, 2022
R DiscoveryArticles Included:  2

One eighth of the bird species in the world is considered globally threatened; the avifauna of Iraq comprises 409 species and is considered as the maj...

Read More

Coronavirus Pandemic

You can also read COVID related content on R COVID-19

R ProductsCOVID-19

ONE PROBLEM . ONE PURPOSE . ONE PLACE

Creating the world’s largest AI-driven & human-curated collection of research, news, expert recommendations and educational resources on COVID-19

COVID-19 Dashboard