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Anatomy of the AGN in NGC 5548. VIII. XMM-Newton's EPIC detailed view of an unexpected variable multilayer absorber
Kaastra, J. S.; Harrison, F. A.; Kriss, G. A. +21 more
In 2013, we conducted a large multi-wavelength campaign on the archetypical Seyfert 1 galaxy NGC 5548. Unexpectedly, this usually unobscured source appeared strongly absorbed in the soft X-rays during the entire campaign, and signatures of new and strong outflows were present in the almost simultaneous UV HST/COS data. Here we carry out a comprehe…
Quantifying the (X/peanut)-shaped structure in edge-on disc galaxies: length, strength, and nested peanuts
Ciambur, Bogdan C.; Graham, Alister W.
X-shaped or peanut-shaped (X/P) bulges are observed in more than 40 per cent of (nearly) edge-on disc galaxies, though to date a robust method to quantify them is lacking. Using Fourier harmonics to describe the deviation of galaxy isophotes from ellipses, we demonstrate with a sample of 11 such galaxies (including NGC 128) that the sixth Fourier …
Beyond spheroids and discs: classifications of CANDELS galaxy structure at 1.4 < z < 2 via principal component analysis
Papovich, Casey; Barro, Guillermo; Grogin, Norman A. +15 more
Important but rare and subtle processes driving galaxy morphology and star formation may be missed by traditional spiral, elliptical, irregular or Sérsic bulge/disc classifications. To overcome this limitation, we use a principal component analysis (PCA) of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, M…
The Contribution of Host Galaxies to the Infrared Energy Output of z ≳ 5.0 Quasars
Lyu, Jianwei; Alberts, Stacey; Rieke, G. H.
The infrared spectral energy distributions of z ≳ 5 quasars can be reproduced by combining a low-metallicity galaxy template with a standard active galactic nucleus (AGN) template. The host galaxy is represented by Haro 11, a compact, moderately low metallicity, starbursting galaxy that shares typical features of high-z galaxies. For the vast majo…
A new model for the X-ray continuum of the magnetized accreting pulsars
Ferrigno, Carlo; Becker, Peter A.; Bozzo, Enrico +1 more
Context. Accreting highly magnetized pulsars in binary systems are among the brightest X-ray emitters in our Galaxy. Although a number of high-quality broad-band (0.1-100 keV) X-ray observations are available, the spectral energy distribution of these sources is usually investigated by adopting pure phenomenological models rather than models linke…
Low-ionization structures in planetary nebulae - I. Physical, kinematic and excitation properties
Gonçalves, Denise R.; Akras, Stavros
Though the low-ionization small-scale structures (LISs) such as knots, filaments and jets of planetary nebulae (PNe) are known for ∼30 yr, some of their observational properties are not well established. In consequence, our ability to include them in the wider context of the formation and evolution of PNe is directly affected. Why most structures …
Origin of central abundances in the hot intra-cluster medium. I. Individual and average abundance ratios from XMM-Newton EPIC
Zhang, Y. -Y.; Kaastra, J. S.; Mernier, F. +5 more
The hot intra-cluster medium (ICM) is rich in metals, which are synthesised by supernovae (SNe) explosions and accumulate over time into the deep gravitational potential well of clusters of galaxies. Since most of the elements visible in X-rays are formed by type Ia (SNIa) and/or core-collapse (SNcc) supernovae, measuring their abundances gives us…
Electron hybrid code simulation of whistler-mode chorus generation with real parameters in the Earth's inner magnetosphere
Katoh, Yuto; Omura, Yoshiharu
We carry out a self-consistent simulation of the generation process of whistler-mode chorus by a spatially one-dimensional electron hybrid code, by assuming the magnetic field inhomogeneity corresponding to L = 4 of the dipole field. Chorus emissions with rising tones are reproduced in the simulation result, while the frequency range, sweep rate, …
Carbon to oxygen ratios in extrasolar planetesimals
Gänsicke, Boris T.; Koester, Detlev; Farihi, Jay +1 more
Observations of small extrasolar planets with a wide range of densities imply a variety of planetary compositions and structures. Currently, the only technique to measure the bulk composition of extrasolar planetary systems is the analysis of planetary debris accreting on to white dwarfs, analogous to abundance studies of meteorites. We present me…
Catalog of positions and B-magnitudes of stars in the circumpolar region of the Northern Sky Survey (FON) project
Andruk, V. M.; Pakuliak, L. K.; Golovnia, V. V. +4 more
The catalog of equatorial coordinates α and δ and B-magnitudes of stars has been created at the Main Astronomical Observatory, National Academy of Sciences of Ukraine (MAO NASU), for the circumpolar region (from 58° to 90°) of the Northern Sky Survey (FON) project within the work on the rational use of resources accumulated in the JDA (Joint Digit…