The X-ray luminous galaxies optically classified as star forming are mostly narrow line Seyfert 1 s
نویسندگان
چکیده
منابع مشابه
X-ray spectral complexity in narrow-line Seyfert 1 galaxies
We present a systematic analysis of the X-ray spectral properties of a sample of 22 “narrow-line” Seyfert 1 galaxies for which data are available from the ASCA public archive. Many of these sources, which were selected on the basis of their relatively narrow Hβ line width (FWHM ≤2000 km/s), show significant spectral complexity in the X-ray band. Their measured hard power-law continua have photo...
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We describe how recent X-ray surveys have led to advances in the understanding of ultrasoft narrow-line Seyfert 1 galaxies. The number of known ultrasoft narrow-line Seyfert 1s has increased greatly in recent years due to X-ray surveys, and it is now possible to obtain high quality 0.1–10 keV spectral and variability measurements for a large number of these galaxies. We generalize some of the c...
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We report on AGN with extremely soft X-ray spectra observed with ROSAT. From their optical emission lines these objects are classiied as narrow-line Seyfert 1 galaxies (NLS1), almost all with extremely large Fe ii/H ratios and relatively narrow optical lines of hydrogen. Our results are based on a systematic ROSAT study of 46 NLS1. 32 of these are located in the elds of view of ROSAT pointings ...
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The ROSAT Ultradeep HRI survey in the Lockman Hole contains a complete sample of 91 X-ray sources with fluxes in the 0.5-2 keV band larger than 1.2 · 10 −15 erg cm −2 s −1 , where over 75 % of the sources are quasars or Seyfert galaxies. During the course of our optical identification work, we have obtained optical spectra of 67 narrow emission line galaxies (NELG), which are physically not ass...
متن کاملThe Narrow-line Region of Seyfert Galaxies: Narrow-line Seyfert 1s versus Broad-line Seyfert 1s
It is known that the spectral energy distribution (SED) of the nuclear radiation of narrow-line Seyfert 1 galaxies (NLS1s) has different shapes with respect to that of ordinary broad-line Seyfert 1 galaxies (BLS1s), particularly in wavelengths of X-ray. This may cause some differences in the ionization degree and the temperature of gas in narrow-line regions (NLRs) between NLS1s and BLS1s. This...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2012
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201118301