Search Publications
SMA High Angular Resolution Imaging of the Lensed Quasar APM 08279+5255
Iono, D.; Wilner, D. J.; Krips, M. +4 more
We present Submillimeter Array observations of the z=3.91 gravitationally lensed broad absorption line quasar APM 08279+5255 which spatially resolve the 1.0 mm (200 µm rest frame) dust continuum emission. At 0.4" resolution, the emission is separated into two components, a stronger, extended one to the northeast (46+/-5 mJy) and a weaker, co…
Dust Rings and Filaments around the Isolated Young Star V1331 Cygni
Quanz, S. P.; Apai, D.; Henning, Th.
We characterize the small- and large-scale environment of the young star V1331 Cygni with high-resolution HST WFPC2 and Digitized Sky Survey images. In addition to a previously known outer dust ring (~30'' in diameter), the WFPC2 scattered light image reveals an inner dust ring for the first time. This ring has a maximum radius of ~6.5<…
Estimating stellar parameters from spectra using a hierarchical Bayesian approach
Aerts, C.; Decin, L.; Molenberghs, G. +1 more
A method is developed for fitting theoretically predicted astronomical spectra to an observed spectrum. Using a hierarchical Bayesian principle, the method takes both systematic and statistical measurement errors into account, which has not been done before in the astronomical literature. The goal is to estimate fundamental stellar parameters and …
Reconstructing Spherical Nonlinear Force-free Field in the Solar Corona
Wu, S. T.; Zhang, H. Q.; Fang, C. +3 more
We present a spherical nonlinear force-free field (NFFF) reconstructing method based on the photospheric vector magnetograms. The importance of this method is its ability to reveal the NFFF configurations, which is necessary for understanding the physical mechanisms of the initiation of the large-scale solar eruptions, such as coronal mass ejectio…
Optical Identification of 15 µm Sources in the AKARI Performance Verification Field toward the North Ecliptic Pole
Im, M.; Lee, H. M.; Inami, H. +28 more
We present the results of optical identifications for 257 mid-infrared sources detected with a deep 15K_{s}
Search for photospheric footpoints of quiet Sun transition region loops
Sütterlin, P.; Teriaca, L.; Schühle, U. +3 more
Context: The footpoints of quiet Sun Transition Region (TR) loops do not seem to coincide with the photospheric magnetic structures appearing in traditional low-sensitivity magnetograms.
Aims: We look for the so-far unidentified photospheric footpoints of TR loops using G-band bright points (BPs) as proxies for photospheric magnetic field conc…
Morphological evolution of z ~ 1 galaxies from deep K-band AO imaging in the COSMOS deep field
Rouan, D.; Huertas-Company, M.; Tasca, L. +3 more
Context: We present the results of an imaging program of distant galaxies (z∼0.8) at high spatial resolution (~0.1'') aiming at studying their morphological evolution. We observed 7 fields of 1'×1' with the NACO Adaptive Optics system (VLT) in Ks (2.16~µm) band with typical V∼14 guide stars and 3 h integration time per field. Obse…
The superrotation of solar supergranules
Meunier, N.; Roudier, T.
Context: Supergranules have long been believed to rotate faster than plasma and than magnetic structures. However, it has recently been shown that this could be due to a bias appearing when using Dopplergrams, which are strongly affected by projection effets.
Aims: Our purpose is to perform new measurements of supergranule angular velocities u…
Velocity Profiles in the Solar Corona from Multi-Instrument Observations
Lamy, P.; Lallement, R.; Quémerais, E. +1 more
We present a method to derive outflow velocities in the solar corona using different data sets, including solar wind mass flux coming from the SWAN SOHO instrument, electron density values from LASCO-C2, and interplanetary solar wind velocities derived from ground-based interplanetary scintillation observations (IPS). In a first step, we combine t…
A Suzaku Observation of the Low-Ionization Fe-Line Emission from RCW 86
Petre, Robert; Kilbourne, Caroline A.; Kokubun, Motohide +14 more
The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant RCW 86 in 2006 February to study the nature of the 6.4keV emission line first detected with the Advanced Satellite for Cosmology and Astronomy (ASCA). The new data confirm the existence of the line, localizing it for the first time; most of the…