Search Publications
A SINFONI integral field spectroscopy survey for galaxy counterparts to damped Lyman α systems - II. Dynamical properties of the galaxies towards Q0302 - 223 and Q1009 - 0026
Bouché, Nicolas; York, Donald G.; Kulkarni, Varsha P. +2 more
Details of the processes through which galaxies convert their gas into stars need to be studied in order to obtain a complete picture of galaxy formation. One way to tackle these phenomena is to relate the H I gas and the stars in galaxies. Here, we present dynamical properties of damped and subdamped Lyman α (DLA) systems identified in Hα emissio…
Low-frequency Observations of Polarized Emission from Long-lived Non-thermal Radio Sources in the Solar Corona
Ramesh, R.; Kathiravan, C.; Narayanan, A. Satya
We report observations of circularly polarized emission from the solar corona at 77 MHz during the periods 2006 August 11-18, 2006 August 23-29, and 2007 May 16-22 in the minimum phase between the sunspot cycles 23 and 24. The observations were carried out with the east-west one-dimensional radio polarimeter at the Gauribidanur observatory located…
Non-adiabatic Ion Acceleration in the Earth Magnetotail and Its Various Manifestations in the Plasma Sheet Boundary Layer
Zelenyi, L. M.; Sauvaud, J. -A.; Owen, C. J. +5 more
Many physical phenomena in space involve energy dissipation which generally leads to charged particle acceleration, often up to very high energies. In the Earth magnetosphere energy accumulation and release occur in the magnetotail, namely in its Current Sheet (CS). The kinetic analysis of non-adiabatic ion trajectories in the CS region with finit…
Non-LTE models for the gaseous metal component of circumstellar discs around white dwarfs
Rauch, T.; Werner, K.; Nagel, T. +1 more
Context. Gaseous metal discs around single white dwarfs have been discovered recently. They are thought to develop from disrupted planetary bodies.
Aims: Spectroscopic analyses will allow us to study the composition of extrasolar planetary material. We investigate in detail the first object for which a gas disc was discovered (SDSS J122859.93…
New constraints on the complex mass substructure in Abell 1689 from gravitational flexion
Goldberg, David M.; Leonard, Adrienne; King, Lindsay J.
In a recent publication, the flexion aperture mass statistic was found to provide a robust and effective method by which substructure in galaxy clusters might be mapped. Moreover, we suggested that the masses and mass profile of structures might be constrained using this method. In this paper, we apply the flexion aperture mass technique to HST AC…
Analysis of Saturn kilometric radiation near a source center
Schippers, P.; Gurnett, D. A.; Lamy, L. +3 more
The Cassini spacecraft flew very near a source region of Saturn kilometric radiation (SKR) on day 73 of 2008, the second known encounter with a source region at high latitude. The radio and plasma wave instrument, Radio and Plasma Wave Science, observed intense kilometric emission in the extraordinary X mode, ordinary O mode, and Z mode. The elect…
Low-altitude acceleration of ionospheric ions at Mars
Barabash, S.; Lundin, R.; Yamauchi, M. +2 more
The objective of this study is to understand the acceleration processes that lead to outflow and escape of ionospheric ions from Mars. Observations show that accelerated dayside and flank ionospheric ions move slowly antisunward along the direction of the external/magnetosheath flow. At high altitudes, in the central tail, ions are further acceler…
SOHO/SWAN Observations of Short-period Spacecraft Target Comets
Bertaux, J. -L.; Combi, M. R.; Quémerais, E. +3 more
SWAN, the Solar Wind ANisotropies all-sky hydrogen Lyα camera on the Solar and Heliospheric Observatory spacecraft that makes all-sky images of interplanetary neutral hydrogen, has an ongoing campaign to make special observations of comets, both short- and long-period ones, in addition to the serendipitous observations of comets as part of the all…
Spectral Cross-Calibration of the Konus-Wind, the Suzaku/WAM, and the Swift/BAT Data Using Gamma-Ray Bursts
Yamaoka, Kazutaka; Ohno, Masanori; Onda, Kaori +20 more
We report on the spectral cross-calibration results of the Konus-Wind, the Suzaku/WAM, and the Swift/BAT instruments using simultaneously observed gamma-ray bursts (GRBs). This is the first attempt to use simultaneously observed GRBs as a spectral calibration source to understand systematic problems among the instruments. Based on these joint spec…
Failed Eruption of a Filament as a Driver for Vertical Oscillations of Coronal Loops
Mrozek, T.
We present observations of a failed eruption of a magnetic flux rope recorded during the M6.2 flare of 14 July 2004. The observations were mainly made with TRACE 171 Å and 1600 Å filters. The flare was accompanied by a destabilization of a magnetic structure observed as a filament eruption. After an initial acceleration, the eruption slowed down a…