搜索结果: 1-15 共查到“天文学 Seyfert”相关记录35条 . 查询时间(0.046 秒)
We present a multiwavelength study of the highly evolved compact galaxy group known as Seyfert's Sextet (HCG79: SS). We interpret SS as a 2-3 Gyr more evolved analog of Stephan's Quintet (HCG92: SQ). ...
Extreme Warm Absorber variability in the Seyfert Galaxy Mrk 704
Galaxies: active – X-rays: galaxies – X-rays: individual: Mrk 704
2011/9/28
In about half of Seyfert galaxies, the X-ray emission is absorbed by an optically thin, ionized medium, the so-called "Warm Absorber", whose origin and location is still a matter of debate. The aims o...
Very Long Baseline Array Imaging of Parsec-scale Jet Structures in Radio-loud Narrow-line Seyfert 1 Galaxies
Long Baseline Array Imaging Radio-loud Narrow-line Seyfert
2011/10/21
We conducted very long baseline interferometry (VLBI) observations of five radio-loud narrow-line Seyfert 1 (NLS1) galaxies in milliarcsecond resolutions at 1.7 GHz (18 cm) using the Very Long Baselin...
Narrow-line Seyfert 1 galaxies: an amasing class of AGN
Masers – Galaxies: active – Galaxies: nuclei – Galaxies: Seyfert – Radio lines: galaxies
2011/10/21
Narrow-line Seyfert 1 (NLS1) galaxies are a class of active galactic nuclei (AGN) that have all the properties of type 1 Seyfert galaxies but show peculiar characteristics, including the narrowest Bal...
On the BH-galaxy relation of AGN and Narrow Line Seyfert 1 Galaxies
BH-galaxy relation AGN Narrow Seyfert Galaxies
2011/10/12
Massive black holes (BHs) are detected in the centers of many nearby galaxies are linearly correlated with the luminosity of the host bulge (spheroid), the black hole mass being about 0.1% of the stel...
Resolving the nuclear dust distribution of the Seyfert 2 galaxy NGC 3081
galaxies: active – galaxies: nuclei – galaxies: imaging – galaxies: indi-vidual
2011/10/8
We report far-infrared (FIR) imaging of the Seyfert 2 galaxy NGC 3081 in the range 70-500 micron, obtained with an unprecedented angular resolution, using the Herschel Space Observatory instruments PA...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
galaxies active – line:profile – X-rays:galaxies
2011/8/24
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei
Grating Observations Seyfert Galaxies Comparison
2011/9/26
We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations ...
The Difference in Narrow Fe KαLine Emission Between Seyfert 1 and Seyfert 2 Galaxies
Narrow Fe KαLine Emission Seyfert 1 Seyfert 2 Galaxies
2011/1/10
We compile a sample of 89 Seyfert galaxies with both [OIV] 25.89 um line luminosities observed by Spitzer IRS and X-ray spectra observed by XMM EPIC. Using [OIV] emission as proxy of AGN intrinsic lum...
X-ray Outflows in the Swift Burst Alert Detected Seyfert 1s
galaxies active—galaxies Seyfert—X-rays galaxies
2010/11/12
Previous surveys of outflows in low-redshift active galactic nuclei (AGN) have relied on the analysis of sources selected primarily for their optical/X-ray brightness, and are therefore biased. Toward...
X-Ray Properties of Narrow-Line Seyfert 1 Galaxies with Very Small Broad-Line Widths
galaxies active— galaxies Seyfert — X-rays galaxies
2010/11/16
Narrow-line Seyfert 1 galaxies (NLS1s) with very small broad-line widths (say,FWHM(H ) . 1200 kms-1) represent the extreme type of Seyfert 1 galaxies that have small black hole masses (MBH) and/or hig...
INTEGRAL observations of the GeV blazar PKS1502+106 and of the hard X-ray bright Seyfert Galaxy Mkn841
galaxies active – quasars individual PKS 1502+106 – Galaxies Seyfert – galaxies individual Mkn 841 – radiation
2010/11/16
Context. Extragalactic nuclear activity is best explored with observations at high energies, where the most extreme flux and spectral variations are expected to occur, witnessing changes in the accret...
Optical multiband surface photometry of a sample of Seyfert galaxies. I. Large-scale morphology and local environment analysis of matched Seyfert and inactive galaxy samples
galaxies Seyfert – galaxies structure – techniques image processing – techniques photometric
2010/11/12
Context. Parallel analysis of the large-scale morphology and local environment of matched active and control galaxy samples plays an important role in studies of the fueling of active galactic nuclei.
The first gamma-ray outburst of a Narrow-Line Seyfert 1 Galaxy: the case of PMN J0948+0022 in July 2010
gamma-ray outburst Narrow-Line Seyfert 1 Galaxy
2011/1/10
We report on a multiwavelength campaign on the radio-loud Narrow-Line Seyfert 1 (NLS1) Galaxy PMN J0948+0022 (z=0.5846) performed in 2010 July-September and triggered by a high-energy gamma-ray outbur...
The X-ray Power Spectral Density Function of the Seyfert Active Galactic Nucleus NGC 7469
High Energy Astrophysical Phenomena (astro-ph.HE)
2011/1/5
We present the broadband X-ray power spectral density function (PSD) of the X-ray-luminous Seyfert 1.2 NGC 7469, measured from Rossi X-ray Timing Explorer monitoring data and two XMM-Newton observatio...