Search Publications
XMM-Newton and Swift observations prove GRB090709A to be a distant, standard, long GRB
Tiengo, A.; de Luca, A.; Götz, D. +4 more
GRB090709A is a long gamma-ray burst (GRB) discovered by Swift, featuring a bright X-ray afterglow as well as a faint infrared transient with very red and peculiar colours. The burst attracted a large interest because of a possible quasi-periodicity at P = 8.1s in the prompt emission, suggesting that it could have a different origin with respect t…
Molecular disks in radio galaxies. The pathway to ALMA
Prandoni, I.; de Ruiter, H. R.; Parma, P. +1 more
Context. It has recently been proposed that the jets of low-luminosity radio galaxies are powered by direct accretion of the hot phase of the IGM onto the central black hole. Cold gas remains a plausible alternative fuel supply, however. The most compelling evidence that cold gas plays a role in fueling radio galaxies is that dust is detected more…
Deep XMM-Newton observation of the η Chamaleontis cluster
López-Santiago, J.; Albacete Colombo, J. F.; López-García, M. A.
Context. The members of the η Chamaleontis cluster are in an evolutionary stage in which disks are rapidly evolving. It also exhibits some peculiarities, such as the large fraction of binaries and accretion disks, probably related to the cluster formation process. Its proximity makes this stellar group an ideal target for studying the relation bet…
A Transition Region Explosive Event Observed in He II with the MOSES Sounding Rocket
Kankelborg, Charles C.; Thomas, Roger J.; Fox, J. Lewis
Transition region explosive events (EEs) have been observed with slit spectrographs since at least 1975, most commonly in lines of C IV (1548 Å, 1550 Å) and Si IV (1393 Å, 1402 Å). We report what we believe to be the first observation of a transition region EE in He II 304 Å. With the Multi-Order Solar EUV Spectrograph (MOSES) sounding rocket, a n…
Study of hot flow anomalies using Cluster multi-spacecraft measurements
Dandouras, I.; Daly, P. W.; Lucek, E. A. +2 more
Hot flow anomalies (HFAs) were first discovered in the early 1980s at the bow shock of the Earth. In the 1990s these features were studied, observed and simulated very intensively and many new missions (Cluster, THEMIS, Cassini and Venus Express) focused the attention to this phenomenon again. Many basic features and the HFA formation mechanism we…
Tracking of Coronal White-Light Events by Texture
Stenborg, G.; Vourlidas, A.; Howard, R. +1 more
The extraction of the kinematic properties of coronal mass ejections (CMEs) from white-light coronagraph images involves a significant degree of user interaction: defining the edge of the event, separating the core from the front or from nearby unrelated structures, etc. To contribute towards a less subjective and more quantitative definition, and…
The Three-Dimensional Morphology of a Corotating Interaction Region in the Inner Heliosphere
Howard, R. A.; Wood, B. E.; Socker, D. G. +1 more
In its three years of operation, the HI2 imagers on the two Solar TErrestrial RElations Observatory (STEREO) spacecraft have imaged many corotating interaction regions (CIRs) in the interplanetary medium, allowing the study of their three-dimensional (3D) morphology. Using an entirely empirical analysis technique, we construct a 3D model of one CI…
Nonlinear force-free modelling: influence of inaccuracies in the measured magnetic vector
Solanki, S. K.; Lagg, A.; Wiegelmann, T. +1 more
Context. Solar magnetic fields are regularly extrapolated into the corona starting from photospheric magnetic measurements that can be affected by significant uncertainty.
Aims: We study how inaccuracies introduced into the maps of the photospheric magnetic vector by the inversion of ideal and noisy Stokes parameters influence the extrapolati…
Multiple harmonic ULF waves in the plasma sheet boundary layer observed by Cluster
RèMe, H.; Owen, C. J.; Keiling, A. +7 more
The passage of the Cluster satellites in a polar orbit through Earth's magnetotail has provided numerous observations of harmonically related Pc 1-2 ULF wave events, with the fundamental near the local proton cyclotron frequency Ωcp. Broughton et al. (2008) reported observations by Cluster of three such events in the plasma sheet bounda…
Some statistical properties of flow bursts in the magnetotail
Kim, Hyun-Sook; Lee, Dae-Young; Ohtani, Shin-Ichi +2 more
We investigated the properties of physical parameters during earthward flow burst (FB) events in the near-Earth magnetic tail. For the investigation, we used the measurements made by two of the Cluster satellites, C1 and C4, from 2001 to 2003 and selected FB events based on a set of strict criteria. First, while we confirmed the well-known fact th…