Search Publications
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…
The host galaxy of GRB 011121: morphology and spectral energy distribution
Pian, E.; Greiner, J.; Salvato, M. +3 more
Aims:We present a detailed study of the host galaxy of GRB 011121 (at z = 0.36) based on high-resolution imaging in 5 broad-band, optical and near-infrared filters with HST and VLT/ISAAC.
Methods: The surface brightness profile of this galaxy is best fitted by a Sersic law with index n ∼ 2-2.5 and a rather large effective radius (~7.5 kpc). Bo…
Dust and molecular content of the lensed quasar, MG0751+2716, at z = 3.2
Kneib, J. -P.; Bremer, M.; Alloin, D. +1 more
Context: Gravitational lenses offer unique opportunities to explore the molecular content around active galactic nuclei at high redshift, through the magnification and gain in angular resolution.
Aims: We study here the molecular and dust content of the high redshift (z=3.2), gravitationally lensed quasar MG0751+2716.
Methods: We used the …
Prominence fine structures in a magnetic equilibrium. III. Lyman continuum in 2D configurations
Heinzel, P.; Anzer, U.; Gunár, S.
Aims:We discuss the behavior of the Lyman continuum profiles studied on the grid of 2D vertical-thread models for prominence fine structures.
Methods: Multilevel non-LTE transfer calculations for a 12-level plus continuum hydrogen model atom are used.
Results: Since the Lyman continuum is formed in regions with different temperatures for d…
Unravelling the morphologies of luminous compact galaxies using the HST/ACS GOODS survey
Flores, H.; Hammer, F.; Rawat, A. +2 more
Context: Luminous Compact Galaxies (LCGs) (MB ≤ -20, R1/2 ≤ 4.5 kpc and EW0(OII) ≥ 15 Å) constitute one of the most rapidly evolving galaxy populations over the last ~8 Gyr history of the universe. Due to their inherently compact sizes, any detailed quantitative analysis of their morphologies has proved to be diffi…
Log-normal intensity distribution of the quiet-Sun FUV continuum observed by SUMER
Curdt, W.; Fontenla, J. M.; Avrett, E. H. +1 more
We analyse observations of the quiet-Sun far ultraviolet (FUV) continuum at various wavelengths near 1430 Å obtained by the SUMER instrument on SOHO. According to semi-empirical atmospheric models this continuum originates from the layers in the chromosphere where the temperature rises from low values at near-radiative equilibrium to a plateau of …
Photometric observations of Rosetta target asteroid 2867 Steins
Lowry, S. C.; Weissman, P. R.; Choi, Y. -J.
Asteroid 2867 Steins is one of two flyby targets of ESA's International Rosetta Mission, launched in March, 2004. We obtained CCD observations of Steins on April 14-16, 2004 at Table Mountain Observatory, California, in order to characterize the asteroid physically, information that is crucial for planning the Steins flyby. This study includes the…
Turbulent propagation of high-energy electrons in a solar coronal loop
Melnikov, V. F.; Stepanov, A. V.; Shibasaki, K. +1 more
Aims:We study the solar flare on 28 August 1999 observed by the Nobeyama Radioheliograph at 17 and 34 GHz and analyze the unusual behavior of microwave source (a coronal loop) after injections of high-energy electrons. The observations reveal a propagation velocity of the emission front along the loop of about 104 km s-1, whi…