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Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
Peterson, Bradley M.; Vestergaard, Marianne
We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy. These mass scaling relationships between line widths and luminosity are based on recently improved empirical relationships between the broad-line …
The SAURON project - IV. The mass-to-light ratio, the virial mass estimator and the Fundamental Plane of elliptical and lenticular galaxies
Krajnović, Davor; Emsellem, Eric; van de Ven, Glenn +12 more
We investigate the well-known correlations between the dynamical mass-to-light ratio (M/L) and other global observables of elliptical (E) and lenticular (S0) galaxies. We construct two-integral Jeans and three-integral Schwarzschild dynamical models for a sample of 25 E/S0 galaxies with SAURON integral-field stellar kinematics to about one effecti…
Cassini Observes the Active South Pole of Enceladus
Burns, J. A.; Neukum, G.; Wagner, R. +22 more
Cassini has identified a geologically active province at the south pole of Saturn's moon Enceladus. In images acquired by the Imaging Science Subsystem (ISS), this region is circumscribed by a chain of folded ridges and troughs at ~55°S latitude. The terrain southward of this boundary is distinguished by its albedo and color contrasts, elevated te…
The Radial Velocity Experiment (RAVE): First Data Release
Gilmore, G.; Freeman, K. C.; Evans, N. W. +51 more
We present the first data release of the Radial Velocity Experiment (RAVE), an ambitious spectroscopic survey to measure radial velocities and stellar atmosphere parameters (temperature, metallicity, and surface gravity) of up to one million stars using the Six Degree Field multiobject spectrograph on the 1.2 m UK Schmidt Telescope of the Anglo-Au…
Long γ-ray bursts and core-collapse supernovae have different environments
Pian, E.; Ferguson, H. C.; Gull, T. R. +30 more
When massive stars exhaust their fuel, they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an even more brilliant relativistic explosion known as a long-duration γ-ray burst. One would then expect that these long γ-ray bursts and core-collapse super…
Elemental abundance survey of the Galactic thick disc
Lambert, David L.; Allende Prieto, Carlos; Reddy, Bacham E.
We have performed an abundance analysis for F- and G- dwarfs of the Galactic thick-disc component. A sample of 176 nearby (d<= 150pc) thick-disc candidate stars was chosen from the Hipparcos catalogue and subjected to a high-resolution spectroscopic analysis. Using accurate radial velocities combined with the Hipparcos astrometry, kinematics (U…
The SAURON project - V. Integral-field emission-line kinematics of 48 elliptical and lenticular galaxies
Bacon, Roland; Krajnović, Davor; Emsellem, Eric +10 more
We present the emission-line fluxes and kinematics of 48 representative elliptical and lenticular galaxies obtained with our custom-built integral-field spectrograph, SAURON, operating on the William Herschel Telescope. Hβ, [OIII]λλ4959,5007 and [NI]λλ5198,5200 emission lines were measured using a new procedure that simultaneously fits both the st…
The Hubble Ultra Deep Field
Ferguson, Henry C.; Koekemoer, Anton M.; Lucas, Ray A. +12 more
This paper presents the Hubble Ultra Deep Field (HUDF), a 1 million s exposure of an 11 arcmin2 region in the southern sky with the Advanced Camera for Surveys on the Hubble Space Telescope using Director's Discretionary Time. The exposure time was divided among four filters, F435W (B435), F606W (V606), F775W (i
Radioactive 26Al from massive stars in the Galaxy
Wang, Wei; Knödlseder, Jürgen; Winkler, Christoph +13 more
Gamma-rays from radioactive 26Al (half-life ~7.2 × 105years) provide a `snapshot' view of continuing nucleosynthesis in the Galaxy. The Galaxy is relatively transparent to such γ-rays, and emission has been found concentrated along its plane. This led to the conclusion that massive stars throughout the Galaxy dominate the pro…
Kinetic Physics of the Solar Corona and Solar Wind
Marsch, Eckart
Kinetic plasma physics of the solar corona and solar wind are reviewed with emphasis on the theoretical understanding of the in situ measurements of solar wind particles and waves, as well as on the remote-sensing observations of the solar corona made by means of ultraviolet spectroscopy and imaging. In order to explain coronal and interplanetary …