Search Publications
The very low-mass population of the Corona Australis and Chamaeleon II star forming regions
Eislöffel, J.; López Martí, B.; Mundt, R.
We present the results of a deep optical survey in the Corona Australis and Chamaeleon II star forming regions. Our optical photometry is combined with available near- and mid-infrared photometry to identify very low-mass candidate members in these dark clouds. In our Chamaeleon II field, only one object exhibits clear Hα emission, but the discrep…
A possible bright blue supernova in the afterglow of GRB 020305
Nugent, P.; Fynbo, J. P. U.; Gorosabel, J. +8 more
We report on ground-based and HST(+STIS) imaging of the afterglow and host galaxy of the Gamma-Ray Burst (GRB) of March 5, 2002. The GRB occurred in a R=25.17 ± 0.14 galaxy, which apparently is part of an interacting system. The lightcurve of the optical afterglow shows a rebrightening, or at least a plateau, 12 16 days after the gamma-ray event. …
RR Lyrae stars: kinematics, orbits and z-distribution
de Boer, K. S.; Maintz, G.
RR Lyrae stars in the Milky Way are good tracers to study the kinematic behaviour and spatial distribution of older stellar populations. A recently established well documented sample of 217 RR Lyr stars with V<12.5 mag, for which accurate distances and radial velocities as well as proper motions from the Hipparcos and Tycho-2 catalogues are ava…
New runaway OB stars with HIPPARCOS
Mdzinarishvili, T. G.; Chargeishvili, K. B.
A Monte Carlo method for detection of runaway OB stars from observational data is proposed. 61 runaway OB star candidates have been detected by an analysis of Hipparcos proper motions. The peculiar tangential and total transverse velocities have been determined for these stars. A list of the detected runaway star candidates is presented. The evide…
Unobscured QSO 2: a new class of objects?
Wolter, A.; Henry, J. P.; Gioia, I. M. +1 more
We present in this paper optical and X-ray follow up observations for three X-ray selected objects extracted from the ROSAT North Ecliptic Pole survey which is a flux-limited, completely identified survey. All three objects have X-ray luminosities in the 1044 erg s-1 regime and show narrow emission lines in their optical disc…
Electron density along a coronal loop observed with CDS/SOHO
Doyle, J. G.; Madjarska, M. S.; Ugarte-Urra, I. +1 more
The analysis of a coronal loop observed by CDS and EIT on board SOHO is presented. The loop was situated above the North-East limb at a latitude of ~48°, being clearly visible in the hottest lines of the dataset, Fe xvi 360.76 Å, i.e. greater than 2 000 000 K. The cooler lines in the sample (i.e. O v 629.73 Å and He i 584.35 Å) showed only a brigh…
X-ray observations of the old open stellar cluster NGC 188
Gondoin, P.
I present the analysis results from XMM-Newton observations of the old open stellar cluster NGC 188, which has an age of about 7 Gyr and a near solar metallicity. 58 X-ray sources were detected in the field of view of the EPIC MOS and pn cameras, and 46 sources are new X-ray detections. Visible counterparts were found for 20 sources including the …
A Virgo high-resolution Hα kinematical survey. I. NGC 4438
Adami, C.; Chemin, L.; Boselli, A. +8 more
New Hα emission-line observations of the Virgo cluster galaxy NGC 4438 are presented. Fabry-Perot interferometry data at an effective angular resolution of ~2 arcsec are used to map the kinematics of the ionized gas in the galaxy. For the first time we obtain a velocity field covering a large area in NGC 4438, much larger than that deduced from pr…
Orbits of new Hipparcos binaries. I
Weigelt, G.; Hofmann, K. -H.; Schertl, D. +4 more
We present first orbits for 6 new Hipparcos binaries. The orbits were determined from speckle interferometric measurements collected mainly at the6m BTAtelescope of the Special Astrophysical Observatory in Zelenchuk. Three of the systems, HIP 11352, HIP 14075 and HIP 14230, have late G- or early K-type components, while HIP 14669 = GJ 125, HIP 106…
New insights in the FUV into the activity of the Herbig Ae star HD 163296
Deleuil, M.; Bouret, J. -C.; Roberge, A. +6 more
We present an analysis of the FUSE spectra of