Search Publications
PPM-Extended (PPMX) - a catalogue of positions and proper motions
Schwan, H.; Scholz, R. -D.; Piskunov, A. E. +3 more
Aims: We build a catalogue PPM-Extended (PPMX) on the ICRS system which is complete down to a well-defined limiting magnitude and contains the best presently available proper motions suited for kinematic studies in the Galaxy.
Methods: We perform a rigorous weighted least-squares adjustment of individual observations, spread over more than a c…
Evolution of tidal disruption candidates discovered by XMM-Newton
Read, A. M.; Esquej, P.; Freyberg, M. J. +8 more
Context: It has been demonstrated that active galactic nuclei are powered by gas accretion onto supermassive black holes located at their centres. The paradigm that the nuclei of inactive galaxies are also occupied by black holes was predicted long ago by theory. In the past decade, this conjecture was confirmed by the discovery of giant-amplitude…
Flows in active region loops observed by Hinode EIS
Del Zanna, G.
We aim to investigate the overall characteristics of coronal active region loops and their evolution. The Hinode database was searched for observations of active regions as they crossed the Sun centre. NOAA 10926 was selected. The morphology of this young active region did not significantly change over the course of a few days. Persistent redshift…
Detection of hot gas in the filament connecting the clusters of galaxies Abell 222 and Abell 223
Finoguenov, A.; Böhringer, H.; Simionescu, A. +4 more
Context: About half of the baryons in the local Universe are invisible and - according to simulations - their dominant fraction resides in filaments connecting clusters of galaxies in the form of low density gas with temperatures in the range of 105 < T < 107 K. This warm-hot intergalactic medium has never been detected…
The nature of UCDs: Internal dynamics from an expanded sample and homogeneous database
Ferrarese, L.; Infante, L.; Rejkuba, M. +9 more
Context: The internal dynamics of ultra-compact dwarf galaxies (UCDs) has attracted increasing attention, with most of the UCDs studied to date located in the Virgo cluster.
Aims: Our aim is to perform a comprehensive census of the internal dynamics of UCDs in the Fornax cluster, and to shed light on the nature of the interface between star cl…
Hipparcos distance estimates of the Ophiuchus and the Lupus cloud complexes
Alves, J.; Lombardi, M.; Lada, C. J.
We combine extinction maps from the Two Micron All Sky Survey (2MASS) with Hipparcos and Tycho parallaxes to obtain reliable and high-precision estimates of the distance to the Ophiuchus and Lupus dark complexes. Our analysis, based on a rigorous maximum-likelihood approach, shows that the ρ-Ophiuchi cloud is located at (119 ± 6) pc and the Lupus …
Multi-wavelength observations of Galactic hard X-ray sources discovered by INTEGRAL. II. The environment of the companion star
Pantin, E.; Chaty, S.; Rahoui, F. +1 more
Context: The INTEGRAL mission has led to the discovery of a new type of supergiant X-ray binaries (SGXBs), whose physical properties differ from those of previously known SGXBs. Those sources are in the course of being unveiled by means of multi-wavelength X-rays, optical, near- and mid-infrared observations, and two classes are appearing. The fir…
X-ray hiccups from Sagittarius A* observed by XMM-Newton. The second brightest flare and three moderate flares caught in half a day
Genzel, R.; Hasinger, G.; Grosso, N. +13 more
Context: Our Galaxy hosts at its dynamical center Sgr A*, the closest supermassive black hole. Surprisingly, its luminosity is several orders of magnitude lower than the Eddington luminosity. However, the recent observations of occasional rapid X-ray flares from Sgr A* provide constraints on the accretion and radiation mechanisms at work close to …
Hinode observations of transverse waves with flows in coronal loops
Wang, T. J.; Ofman, L.
Aims: We report the first evidence for transverse waves in coronal multithreaded loops with cool plasma ejected from the chromosphere flowing along the threads. These observations are good candidates for coronal seismology.
Methods: We analyzed observations made with Solar Optical Telescope (SOT) on board the Hinode satellite in the Ca II H li…
IMAGES. III. The evolution of the near-infrared Tully-Fisher relation over the last 6 Gyr
Cesarsky, C.; Östlin, G.; Yang, Y. +22 more
Using the multi-integral field spectrograph GIRAFFE at VLT, we have derived the K-band Tully-Fisher relation (TFR) at z ∼ 0.6 for a representative sample of 65 galaxies with emission lines (W_0(OII)≥15 Å). We confirm that the scatter in the z ∼ 0.6 TFR is caused by galaxies with anomalous kinematics, and find a positive and strong correlation betw…