Search Publications
Heliospheric interstellar H temperature from SOHO/SWAN H cell data
Schmidt, W.; Bertaux, J. -L.; Lallement, R. +3 more
We show a first comparison between selected SOHO/SWAN H cell data recorded in 1996-1997 and a simple classical ``hot model'' of the interstellar (IS) H flow in the inner heliosphere. Our goal is to obtain some constraints on the interplanetary background Ly-alpha profiles, for the first time without any assumption on the H cell characteristics. Fo…
The physical properties of the HH 30 jet from HST and ground-based data
Bacciotti, Francesca; Eislöffel, Jochen; Ray, Thomas P.
We investigate the physical properties of the HH 30 jet by applying the spectroscopic diagnostic technique described in Bacciotti & Eislöffel (\cite{be99}) to ground-based spectra and Hubble Space Telescope (HST) calibrated emission-line images. We derive the variation along the beam of the ionization fraction xe, of the total hydro…
Optical imaging of the host galaxies of X-ray selected BL Lacertae objects
Falomo, Renato; Kotilainen, Jari K.
We investigate the properties of the host galaxies of X-ray selected (high frequency peaked) BL Lac objects using a large and homogeneous data set of high spatial resolution R-band observations of 52 BL Lacs in the EMSS and Slew samples. The redshift distribution of the BL Lacs ranges from z = 0.04 to z>0.7, with average and median redshifts z …
The chemical composition of the silicate dust around RAFGL7009S and IRAS 19110+1045
Cox, P.; Dartois, E.; Demyk, K. +2 more
We have studied the chemical composition of the silicates around the two massive protostellar objects RAFGL7009S (IRAS 18316-0602) and IRAS 19110+1045. The silicate features of both sources are similar. The position and shape of the 9.6 and 18 mu m silicate bands coincide with those of amorphous pyroxene-type silicates. We find that the silicate f…
Detection of HD in the Orion molecular outflow
Wright, Christopher M.; Bertoldi, Frank; Timmermann, Ralf +2 more
We report a detection in the interstellar medium of an infrared transition within the electronic ground state of the deuterated hydrogen molecule, HD. Through a deep integration with the Short-Wavelength-Spectrometer (SWS) on board the Infrared Space Observatory (ISO), the pure rotational v=0-0 R(5) line at 19.43 mu m was detected toward the Orion…
On the origin of [O iv] emission in Wolf-Rayet galaxies
Schaerer, Daniel; Stasińska, Grażyna
We propose that the emission of the high excitation [O iv] 25.9 mu m line observed with ISO in
The ISO spectrum of the planetary nebula NGC 6302. II. Nebular abundances
Pottasch, S. R.; Beintema, D. A.
The ISO spectrum of NGC 6302 is used, in conjunction with the visible and ultraviolet spectrum, to determine the nebular composition. In addition to being considerably more accurate than previous determinations, the abundances of many more elements (and ions) can be found. A discussion of the previous evolution of the central star, in the light of…
The quiet Sun extreme ultraviolet spectrum observed in normal incidence by the SOHO coronal diagnostic spectrometer
Harrison, R. A.; Landini, M.; Innes, D. E. +10 more
The extreme ultraviolet quiet Sun spectrum, observed at normal incidence by the Coronal Diagnostic Spectrometer on the SOHO spacecraft, is presented. The spectrum covers the wavelength ranges 308-381 Ä and 513-633 Ä and is based on data recorded at various positions on the solar disk between October 1996 and February 1997. Datasets at twelve of th…
The NTT SUSI deep field
Fontana, A.; Cristiani, S.; Giallongo, E. +3 more
We present a deep BVrI multicolor catalog of galaxies in a 5.62 sq.arcmin field 80 arcsec south of the high redshift (z=4.7) quasar BR 1202-0725, derived from observations with the direct CCD camera SUSI at the ESO NTT. The formal 5sigma magnitude limits (in 2x FWHM apertures) are 26.9, 26.5, 25.9 and 25.3 in B, V, r and I respectively. Counts, co…
A ring galaxy at z=1 lensed by the cluster Abell 370
Altieri, B.; Metcalfe, L.; Kneib, J. P. +3 more
We present a study of a very peculiar object found in the field of the cluster-lens Abell 370. This object displays, in HST imaging, a spectacular morphology comparable to nearby ring-galaxies. From spectroscopic observations at the CFHT, we measured a redshift of z=1.062 based on the identification of [Oii] 3727 Angstroms and [Nev] 3426 Angstroms…