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The origin of blueshifted absorption features in the X-ray spectrum of PG 1211+143: outflow or disc.
Fabian, A. C.; Gallo, L. C.
In some radio-quiet active galactic nuclei (AGN), high-energy absorption features in the X-ray spectra have been interpreted as ultrafast outflows (UFOs) - highly ionized material (e.g. Fe XXV and Fe XXVI) ejected at mildly relativistic velocities. In some cases, these outflows can carry energy in excess of the binding energy of the host galaxy. N…
A Multi-wavelength Analysis of Active Regions and Sunspots by Comparison of Automatic Detection Algorithms
Verbeeck, C.; Delouille, V.; Colak, T. +4 more
Since the Solar Dynamics Observatory (SDO) began recording ≈ 1 TB of data per day, there has been an increased need to automatically extract features and events for further analysis. Here we compare the overall detection performance, correlations between extracted properties, and usability for feature tracking of four solar feature-detection algor…
Dynamics of Large Fragments in the Tail of Active Asteroid P/2010 A2
Jewitt, David; Agarwal, Jessica; Weaver, Harold
We examine the motions of large fragments at the head of the dust tail of the active asteroid P/2010 A2. In previous work, we showed that these fragments were ejected from the primary nucleus in early 2009, either following a hypervelocity impact or by rotationally induced breakup. Here, we follow their positions through a series of Hubble Space T…
Investigating the Potential Dilution of the Metal Content of Hot Gas in Early-type Galaxies by Accreted Cold Gas
Irwin, Jimmy A.; Su, Yuanyuan
The measured emission-weighted metal abundance of the hot gas in early-type galaxies has been known to be lower than theoretical expectations for 20 years. In addition, both X-ray luminosity and metal abundance vary significantly among galaxies of similar optical luminosities. This suggests some missing factors in the galaxy evolution process, esp…
Dynamical and physical properties of 22 binaries discovered by W. S. Finsen
Docobo, J. A.; Andrade, M.
Using recent speckle measurements performed by different observers, in this paper we present revised orbital elements and dynamical masses for the binaries WDS 02396-1152 (FIN 312), 04515-3454 (FIN 320), 06253+0130 (FIN 343), 07003-2207 (FIN 334 Aa,Ab), 08291-4756 (FIN 315 Aa,Ab), 08345-3236 (FIN 335), 09173-6841 (FIN 363 AB), 09442-2746 (FIN 326)…
The extended Saturnian neutral cloud as revealed by global ENA simulations using Cassini/MIMI measurements
Krupp, N.; Krimigis, S. M.; Mitchell, D. G. +4 more
We show that the neutral gas vertical distribution at Saturn must be ~3-4 times more extended than previously thought for the >5 RSregions, while the neutral H distribution is consistent with H densities that reach up to ~150/cm3close to the orbit of Titan. We utilize a technique to retrieve the global neutral gas distribu…
The Optical Colors of Giant Elliptical Galaxies and their Metal-Rich Globular Clusters Indicate a Bottom-Heavy Initial Mass Function
Kruijssen, J. M. Diederik; Goudfrooij, Paul
We report a systematic and statistically significant offset between the optical (g - z or B - I) colors of seven massive elliptical galaxies and the mean colors of their associated massive metal-rich globular clusters (GCs) in the sense that the parent galaxies are redder by ~0.12-0.20 mag at a given galactocentric distance. However, spectroscopic…
Electron demagnetization and heating in quasi-perpendicular shocks
Mozer, F. S.; Sundkvist, D.
Field and plasma measurements made during a quasi-perpendicular terrestrial bow shock crossing by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) E spacecraft on 21 August 2010 show that the measured electric field, being as great as 300 mV/m in the ramp, produced potential fluctuations over an electron gyrodiamete…
Testing the dipole modulation model in CMBR
Jain, Pankaj; Rath, Pranati K.
The hemispherical power asymmetry, observed in the CMBR data, has generally been interpreted in terms of the dipole modulation model for the temperature fluctuations. Here we point out that this model leads to several predictions, which can be directly tested in the current data. We suggest tests of the hemispherical power asymmetry both in real a…
Helioseismology of Pre-emerging Active Regions. I. Overview, Data, and Target Selection Criteria
Leka, K. D.; Barnes, G.; Birch, A. C. +4 more
This first paper in a series describes the design of a study testing whether pre-appearance signatures of solar magnetic active regions were detectable using various tools of local helioseismology. The ultimate goal is to understand flux-emergence mechanisms by setting observational constraints on pre-appearance subsurface changes, for comparison …