Search Publications
Hydrogen infrared recombination lines as a diagnostic tool for the geometry of the circumstellar material of hot stars
Waters, L. B. F. M.; de Koter, A.; Lenorzer, A.
We have analysed the infrared hydrogen recombination lines of a sample of well studied hot massive stars observed with the Infrared Space Observatory. Our sample contains stars from several classes of objects, whose circumstellar environment is believed to be dominated by an ionized stellar wind (the Luminous Blue Variables) or by a dense disk-lik…
XMM-Newton observation of a distant X-ray selected cluster of galaxies at z=1.26 with possible cluster interaction
Rosati, Piero; Hashimoto, Yasuhiro; Miyaji, Takamitsu +2 more
We report on the XMM-Newton observation of RX J1053.7+5735, one of the most distant (z = 1.26) X-ray selected clusters of galaxies, which also shows an unusual double-lobed X-ray morphology, indicative of possible cluster-cluster interaction. The cluster was discovered during our ROSAT deep pointings in the direction of the Lockman Hole. The XMM-N…
The ISO-LWS map of the Serpens cloud core. II. The line spectra
Liseau, R.; Larsson, B.; Men'shchikov, A. B.
We present spectrophotometric ISO imaging with the LWS and the CAM-CVF of the Serpens molecular cloud core. The LWS map is centred on the far infrared and submillimetre source FIRS 1/SMM 1 and its size is 8',x 8'. The fine structure line emission in [O I] 63 mu m and [C II] 157 mu m is extended on the arcminute scale and can …
Abundances of Planetary Nebula NGC 5315
Pottasch, S. R.; Beintema, D. A.; Feibelman, W. A. +2 more
The ISO and IUE spectra of the elliptical nebula
Multi wavelength investigation of the eruption of a sigmoidal quiescent filament
Delaboudinière, J. P.; Marqué, Ch.; Lantos, P.
We report the first observation of a filament eruption in the metric and decimetric range, where the behavior of the filament can be followed during the event via thermal radio emission diagnostics. The event, occurring on February 28th 2001, involved a quiescent filament in a sigmoid magnetic configuration, whose eruption is triggered by the birt…
BL Lac identification for the ultraluminous X-ray source observed in the direction of NGC 4698
Palazzi, E.; Cappi, M.; Martini, P. +11 more
We report the identification of the optical and radio counterparts of the ultraluminous X-ray (ULX) source XMMU J124825.9+083020 (NGC 4698-ULX1). The optical spectrum taken with the VLT yields a redshift of z=0.43, which implies that the ULX is not associated with the nearby galaxy NGC 4698. The spectral energy distribution calculated from the ava…
Exploring the spectral properties of faint hard X-ray sources with XMM-Newton
Fiore, F.; Cappi, M.; Piconcelli, E. +3 more
We present a spectroscopic study of 41 hard X-ray sources detected serendipitously with high significance (>5sigma in the 2-10 keV band) in seven EPIC performance/verification phase observations. The large collecting area of EPIC allows us to explore the spectral properties of these faint hard X-ray sources with 2 < F2-10 < 80 …
Properties of ultraviolet lines observed with the Coronal Diagnostic Spectrometer (CDS/SOHO) in coronal holes and the quiet Sun
Solanki, S. K.; Brković, A.; Schühle, U. +4 more
We present an analysis of 14 ultraviolet emission lines belonging to different atoms and ions observed inside polar coronal holes and in the normal quiet Sun. The observations were made with the Coronal Diagnostic Spectrometer (CDS) onboard the Solar and Heliospheric Observatory (SOHO). This study extends previous investigations made with the Sola…
H2O in stellar atmospheres. II. ISO spectra of cool red giants and hydrostatic models
Kerschbaum, F.; Aringer, B.; Jörgensen, U. G.
We present 26 ISO-SWS spectra taken from a sample of 13 M-type Semiregular, Lb and Mira variables and covering the wavelength range between 2.36 and 5 mu m at a medium resolution. All of the studied objects show intense water bands producing a deep absorption dip around 2.5 mu m. Features of CO, OH, SiO and CO2 are also visible. Using t…
ISO LWS Spectra of T Tauri and Herbig AeBe stars
van Dishoeck, E. F.; Blake, G. A.; Chiang, E. I. +2 more
We present an analysis of ISO-LWS spectra of eight T Tauri and Herbig AeBe young stellar objects. Some of the objects are in the embedded phase of star-formation, whereas others have cleared their environs but are still surrounded by a circumstellar disk. Fine-structure lines of [OI] and [CII] are most likely excited by far-ultraviolet photons in …