Chandra Observations of Ngc 4698: a Seyfert 2 Galaxy with No Absorption

نویسندگان

  • I. Georgantopoulos
  • A. Zezas
چکیده

We present Chandra ACIS-S observations of the enigmatic Seyfert 2 galaxy NGC 4698. This object, together with several other bona fide Seyfert 2 galaxies, shows no absorption in the low spatial resolution ASCA data, in contrast to the standard unification models. Our Chandra observations of NGC 4698 probe directly the nucleus, allowing us to check whether nearby sources contaminate the ASCA spectrum. Indeed, the Chandra observations show that the ASCA spectrum is dominated by two nearby AGNs. The X-ray flux of NGC 4698 is dominated by a nuclear source with luminosity L0:3 8 keV 1039 ergs s 1, coincident with the radio nucleus. Its spectrum is well represented by a power law, 2:2, obscured by a small column density of 5 1020 cm 2, suggesting that NGC 4698 is an atypical Seyfert galaxy. On the basis of its low luminosity, we then interpret NGC 4698 as a Seyfert galaxy that lacks a broad-line region. Subject headings: galaxies: active — galaxies: individual (NGC 4698) — galaxies: nuclei — quasars: general

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Chandra Grating Observations of Seyfert 1 Galaxies

We present new results from a Chandra HETG observation of NGC 5548 and give a comparison of absorption and emission features found in Seyfert 1 galaxies using Chandra grating observations. Deep soft X-ray edges are seen in Mkn 509 and NGC 3783, consistent with ASCA data. In NGC 5548 and NGC 4501 the edges are weak but consistent with the low column densities. We show that the detection of a nar...

متن کامل

ar X iv : a st ro - p h / 06 06 46 1 v 1 2 0 Ju n 20 06 Chandra Observations of Candidate “ True ” Seyfert 2 Nuclei

The Unification Model for active galactic nuclei posits that Seyfert 2s are intrinsically like Seyfert 1s, but that their broad-line regions (BLRs) are hidden from our view. A Seyfert 2 nucleus that truly lacked a BLR, instead of simply having it hidden, would be a so-called “true” Seyfert 2. No object has as yet been conclusively proven to be one. We present a detailed analysis of four of the ...

متن کامل

Tracking the Complex Absorption in Ngc 2110 with Two Suzaku Observations

We present spectral analysis of two Suzaku observations of the Seyfert 2 galaxy, NGC 2110. This source has been known to show complex, variable absorption which we study in depth by analyzing these two observations set seven years apart and by comparing to previously analyzed observations with the XMM-Newton and Chandra observatories. We find that there is a relatively stable, full-covering abs...

متن کامل

a st ro - p h / 06 06 46 1 v 1 20 J un 2 00 6 Chandra Observations of Candidate “ True ” Seyfert 2 Nuclei

The Unification Model for active galactic nuclei posits that Seyfert 2s are intrinsically like Seyfert 1s, but that their broad-line regions (BLRs) are hidden from our view. A Seyfert 2 nucleus that truly lacked a BLR, instead of simply having it hidden, would be a so-called “true” Seyfert 2. No object has as yet been conclusively proven to be one. We present a detailed analysis of four of the ...

متن کامل

New Chandra/ HST-STIS results on Seyfert I AGN: Photoionized Outflows

We present soft X-ray results from observations with Chandra (HETGS) of the Seyfert I AGN NGC 4593 and Mrk 509. We discuss the photoionized outflows associated with Seyfert I AGN in terms of their absorption spectral signatures and discuss their kinematics, column density and ionization state. We discuss the link between UV and X-ray absorbers in Mrk 509 (which was simultaneously observed with ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2003