Search Publications
The HD 163296 Circumstellar Disk in Scattered Light: Evidence of Time-Variable Self-Shadowing
Illingworth, Garth D.; Ardila, David R.; Krist, John E. +5 more
We present the first multicolor view of the scattered light disk of the Herbig Ae star HD 163296, based on coronagraphic observations from the Hubble Space Telescope Advanced Camera for Surveys (HST ACS). Radial profile fits of the surface brightness along the disk's semimajor axis indicate that the disk is not continuously flared, and extends to …
Modeling Ultraviolet Wind Line Variability in Massive Hot Stars
Blomme, R.; Lobel, A.
We model the detailed time-evolution of discrete absorption components (DACs) observed in P Cygni profiles of the Si IV λ1400 resonance doublet lines of the fast-rotating supergiant HD 64760 (B0.5 Ib). We adopt the common assumption that the DACs are caused by corotating interaction regions (CIRs) in the stellar wind. We perform 3D radiative trans…
The history of mass assembly of faint red galaxies in 28 galaxy clusters since z = 1.3
Andreon, S.
We measure the relative evolution of the number of bright and faint (as faint as 0.05L*) red galaxies in a sample of 28 clusters, out of which 16 are at 0.50 <= z <= 1.27, all observed through a pair of filters bracketing the 4000-Å break rest frame. The abundance of red galaxies, relative to bright ones, is constant over all the studied red…
Location of the bow shock and ion composition boundaries at Venus—initial determinations from Venus Express ASPERA-4
Coates, A. J.; Kallio, E.; Fedorov, A. +52 more
For the first time since 1992 when the Pioneer Venus Orbiter (PVO) ceased to operate, there is again a plasma instrument in orbit around Venus, namely the ASPERA-4 flown on Venus Express (inserted into an elliptical polar orbit about the planet on April 11, 2006). In this paper we report on measurements made by the ion and electron sensors of ASPE…
Relationship between EIT Posteruption Arcades, Coronal Mass Ejections, the Coronal Neutral Line, and Magnetic Clouds
Yurchyshyn, Vasyl
There is observational evidence that the elongation of an Earth-directed coronal mass ejection (CME) may indicate the orientation of the underlying erupting flux rope. In this study, we compare orientations of CMEs, magnetic clouds (MCs), EIT (EUV Imaging Telescope) posteruption arcades, and the coronal neutral line (CNL). We report on good correl…
Realistic simulations of gravitational lensing by galaxy clusters: extracting arc parameters from mock DUNE images
Heymans, C.; De Lucia, G.; Grazian, A. +6 more
Aims: We present a newly developed code that allows simulations of optical observations of galaxy fields with a variety of instruments. The code incorporates gravitational lensing effects and is targeted at simulating lensing by galaxy clusters. Our goal is to create the tools required for comparing theoretical expectations with observations to be…
Plasmoids in Saturn's magnetotail
Lewis, G. R.; Coates, A. J.; Russell, C. T. +10 more
Plasmoids in Saturn's magnetotail are identified by a reversal (northward turning) of the normally southward component of the magnetic field across the tail current sheet. Three large plasmoids have been identified by the Cassini magnetometer, one near 0300 local time at a planet-centered distance of 44 RS and two near midnight at 48-49…
Topological Departures from Translational Invariance along a Filament Observed by THEMIS
Aulanier, G.; Bommier, V.; Schmieder, B. +2 more
We study the topology of the 3D magnetic field in a filament channel to address the following questions: Is a filament always formed in a single flux tube? How does the photospheric magnetic field lead to filament interruptions and to feet formation? What is the relation between feet-related field lines and the parasitic polarities? What can topol…
Exploring the Evolutionary Paths of the Most Massive Galaxies since z ~ 2
Barro, Guillermo; Pérez-González, Pablo G.; Conselice, Christopher J. +3 more
We use Spitzer MIPS data from the FIDEL Legacy Project in the extended Groth strip to analyze the stellar mass assembly of massive (M > 1011 M⊙) galaxies at z < 2 as a function of structural parameters. We find 24 µm emission for more than 85% of the massive galaxies morphologically classified as disks, and for mo…
A review of the quantitative links between CMEs and magnetic clouds
Démoulin, P.
Magnetic clouds (MCs), and more generally, interplanetary coronal mass ejections (ICMEs), are believed to be the interplanetary counterparts of CMEs. The link has usually been shown by taking into account the CME launch position on the Sun, the expected time delay and by comparing the orientation of the coronal and interplanetary magnetic field. M…