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Off-Axis Energy Variability of AGNs: a New Paradigm for Broad-Line- and Continuum-Emitting Regions
accretion, accretion disks—black hole physics—galaxies: active— galaxies: Seyfert — polarization — quasars: emission lines
2011/10/17
The general picture of how thermal AGNs work has become clearer in recent years but major observational puzzles threaten to undermine this picture. These puzzles include AGNs with extremely asymmetric...
The Nature and Cause of Spectral Variability in LMC X-1
Nature Cause Spectral Variability LMC X-1
2011/10/21
We present the results of a long-term observation campaign of the extragalactic wind-accreting black-hole X-ray binary LMC X-1, using the Proportional Counter Array on the Rossi X-Ray Timing Explorer ...
The Orbital Period and Variability of the Dwarf Nova ES Draconis
stars: individual: ES Dra (PG 1524+622) – novae: cataclysmic variables – binaries: spectroscopic – AAVSO
2011/10/12
A radial velocity study of the cataclysmic variable ES Dra (PG 1524+622) is presented. ES Dra is found to have an orbital period of 0.17660 \pm 0.00006 d (4.2384 \pm 0.0014 h). The mass-losing seconda...
Velocity Structure and Variability of [O III] Emission in Black Hole Host Globular Cluster RZ2109
Velocity Structure Variability Emission Globular Cluster
2011/10/12
We present a multi-facility study of the optical spectrum of the extragalactic globular cluster RZ2109, which hosts a bright black hole X-ray source. The optical spectrum of RZ2109 shows strong and ve...
The effects of X-ray absorption variability in NGC 4395
galaxies: active – galaxies: individual: NGC 4395 – X-rays: galaxies
2011/10/8
We present a new X-ray analysis of the dwarf Seyfert galaxy NGC 4395, based on two archival XMM-Newton and Suzaku observations. This source is well known for a series of remarkable properties: one of ...
Dual-Frequency Observations of 140 Compact, Flat-Spectrum Active Galactic Nuclei for Scintillation-Induced Variability
Flat-Spectrum Active Galactic Nuclei Variability
2011/10/8
The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z > 2, indicating an apparent increase in angu...
Variability of the SiO thermal line emission toward the young L1448-mm outflow
Variability SiO emission L1448-mm outflow
2011/10/8
The detection of narrow SiO thermal emission toward young outflows has been proposed to be a signature of the magnetic precursor of C-shocks. Recent modeling of the SiO emission across C-shocks predic...
Variability of C III and Si III lines in the ultraviolet spectral region of the magnetic Bp star a Centauri
Variability ultraviolet spectral region magnetic Centauri
2011/9/30
The variability of twice ionized lines of carbon and silicon in the ultraviolet spectral region of the magnetic Bp star a Centauri is investigated. This study is based on the archival {\it Internation...
Can Self Organized Critical Accretion Disks Generate a Log-normal Emission Variability in AGN?
Accretion accretion disks
2011/9/29
Active Galactic Nuclei (AGN), such as Seyfert galaxies, quasars, etc., show light variations in all wavelength bands, with various amplitude and in many time scales. The variations usually look errati...
The Allen Telescope Array Pi GHz Sky Survey II. Daily and Monthly Monitoring for Transients and Variability in the Bootes Field
Monthly Monitoring Transients Variability Bootes Field
2011/9/29
We present results from daily radio continuum observations of the Bootes field as part of the Pi GHz Sky Survey (PiGSS). These results are part of a systematic and unbiased campaign to characterize va...
Multiwavelength campaign on Mrk 509. IV. Optical-UV-X-ray variability and the nature of the soft X-ray excess
galaxies: active – galaxies: nuclei – galaxies: Seyfert – quasars: individual: Mrk 509 – X-rays: galaxies
2011/9/27
We present the analysis of XMM-Newton and Swift optical-UV and X-ray observations of the Seyfert-1/QSO Mrk 509, part of an unprecedented multi-wavelength campaign, investigating the nuclear environmen...
Multiwavelength campaign on Mrk 509. I. Variability and spectral energy distribution
Galaxies: active – quasars: absorption lines – X-rays: general
2011/9/27
(Abridged) Active galactic nuclei show a wealth of interesting physical processes, some of which are poorly understood. We want to address a number of open questions, including the location and physic...
Discovering the missing 2.2ars by combining optical variability and optical/near-IR colors
Discovering missing quasars combining variability optical/near-IR colors
2011/9/27
The identifications of quasars in the redshift range 2.2are known to be very inefficient as their optical colors are indistinguishable from those of stars. Recent studies have proposed to use opt...
Variability in the CoRoT photometry of three hot O-type stars. HD 46223, HD 46150 and HD 46966
stars: variables: general – stars: early-type – stars: individual: HD 46223 – stars: individual: HD 46150 – stars: individual: HD 46966 – stars: oscillations
2011/9/27
The detection of pulsational frequencies in stellar photometry is required as input for asteroseismological modelling. The second short run (SRa02) of the CoRoT mission has provided photometric data o...
Varying disc-magnetosphere coupling as the origin of pulse profile variability in SAX J1808.4-3658
accretion accretion discs – pulsars:individual:SAX J1808.4–3658 – stars:neu-tron – X-rays:binaries
2011/9/26
Accreting millisecond pulsars show significant variability of their pulse profiles, especially at low accretion rates. On the other hand, their X-ray spectra are remarkably similar with not much varia...