Search Publications
Constraints on the abundance of solid O_2 in dense clouds from ISO-SWS and ground-based observations
Burgdorf, M.; van Dishoeck, E. F.; Whittet, D. C. B. +9 more
The Short Wavelength Spectrometer (SWS) on-board the Infrared Space Observatory (ISO) has been used to search for solid O_2 in cold dense clouds at 6.45 mu m. Additional constraints on the O_2 abundance are obtained from analysis of the 4.67 mu m solid CO absorption profile observed from the ground. We derive upper limits of 50% and 100% of solid …
Infrared spectroscopy of young supernova remnants heavily interacting with the interstellar medium. I. Ionized species in RCW 103
Lutz, D.; Sturm, E.; Oliva, E. +2 more
ISO spectral observations of the supernova remnant RCW103 are presented. This object is the prototype of relatively young remnants ( ~ 10(3) yr) with fast shocks (v_s ~ 1000 km s(-1) ) interacting with dense interstellar medium. The spectrum is dominated by prominent lines of [NeII], [SiII], [FeII] and other low excitation species which provide, f…
Indications on the binary nature of individual stars derived from a comparison of their HIPPARCOS proper motions with ground-based data. I. Basic principles
Wielen, R.; Dettbarn, C.; Jahreiß, H. +2 more
We present a method which provides some information on the possible binary nature of an apparently single star. The method compares the instantaneously measured HIPPARCOS proper motion with the long-term averaged, ground-based proper motion or with the proper motion derived from old ground-based positions and the HIPPARCOS position. Good sources f…
A study of extreme ultraviolet blinker activity
Harrison, R. A.; Innes, D. E.; Brooks, D. H. +1 more
In a previous paper (Harrison, 1997a), we reported on the existence of extreme ultraviolet (EUV) flashes, known as blinkers, which were identified in the quiet Sun network using the CDS instrument on board the Solar and Heliospheric Observatory. Since then a number of dedicated observations have been made and we report here on an analysis of 97 bl…
Identification of beta -meteoroids from measurements of the dust detector onboard the ULYSSES spacecraft
Mann, I.; Wehry, A.
We investigate the detection of beta -meteoroids (i.e. dust particles that leave the Solar system in unbound orbits from the direction of the Sun) in the data set of the Ulysses dust experiment. Analysis of the detection geometry of the experiment for the time span from launch until the end of 1995 shows that the detection of beta -meteoroids is p…
Astrometric radial velocities. I. Non-spectroscopic methods for measuring stellar radial velocity
Lindegren, Lennart; Madsen, Søren; Dravins, Dainis
High-accuracy astrometry permits the determination of not only stellar tangential motion, but also the component along the line-of-sight. Such non-spectroscopic (i.e. astrometric) radial velocities are independent of stellar atmospheric dynamics, spectral complexity and variability, as well as of gravitational redshift. Three methods are analysed:…
Ultraviolet observations of Sirius A and Sirius B with HST-GHRS. an interstellar cloud with a possible low deuterium abundance
Koester, D.; Ferlet, R.; Vidal-Madjar, A. +4 more
We present new observations of the binary Sirius A / Sirius B performed with HST-GHRS. Two interstellar clouds are detected on this sightline, one of them being identified as the Local Interstellar Cloud (LIC), in agreement with previous HST-GHRS observations of Sirius A (Lallement et al. \cite{lalle}). The interstellar structure of this sightline…
ISO observations of obscured Asymptotic Giant Branch stars in the Large Magellanic Cloud
Waters, L. B. F. M.; Blommaert, J. A. D. L.; van Loon, J. Th. +8 more
We present ISO photometric and spectroscopic observations of a sample of 57 bright Asymptotic Giant Branch stars and red supergiants in the Large Magellanic Cloud, selected on the basis of IRAS colours indicative of high mass-loss rates. PHOT-P and PHOT-C photometry at 12, 25 and 60 mu m and CAM photometry at 12 mu m are used in combination with q…
Strong H_2O and high-J CO emission towards the Class 0 protostar L1448-mm
Liseau, R.; White, G. J.; Benedettini, M. +9 more
The spectrum of the Class 0 source L1448-mm has been measured over the wavelength range extending from 6 to 190 mu m with the Long Wavelength Spectrometer (LWS) and the Short Wavelength Spectrometer (SWS) on the Infrared Space Observatory (ISO). The far infrared spectrum is dominated by strong emission from gaseous H_2O and from CO transitions wit…
Infrared emission of hot water in the atmosphere of Mira
Yamamura, I.; de Jong, T.; Cami, J.
The ISO/SWS spectrum of