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ISO-LWS observations of Herbig Ae/Be stars. I. Fine structure lines
Liseau, R.; White, G. J.; Palla, F. +15 more
We present the results of the first spectrophotometric survey of a sample of eleven Herbig Ae/Be stars (HAEBE) obtained with the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory (ISO). The [OI] 63mu m and the [CII] 158mu m lines are observed in all the investigated sources, while the [OI] 145mu m transition, due to its re…
Global X-ray emission and central properties of early type galaxies
Pellegrini, S.
Hubble Space Telescope observations have revealed that the central surface brightness profiles of early type galaxies can be divided into two types: ``core" profiles and featureless power law profiles, without cores. On the basis of this and previous results, early type galaxies have been grouped into two families. One consists of coreless galaxie…
200-µm ISO observations of NGC 6946: evidence for an extended distribution of cold dust
Bianchi, S.; Davies, J. I.; Evans, R. +2 more
We have used the Infrared Space Observatory (ISO) to obtain a resolved 200-µm image of the nearby spiral galaxy NGC 6946. We compare these observations with those made at 60 and 100 µm by the Infrared Astronomical Satellite (IRAS). Whereas IRAS mainly detected warm dust (T ~ 30 K) heated by star-forming regions, ISO detects an extended…
The Orbit of 16 Cygni AB
Marcy, Geoffrey W.; Hauser, Heather M.
The high orbital eccentricity of the planet around 16 Cygni B may have been induced by the companion star, 16 Cygni A, but only if the stellar binary has sufficiently small periastron distance. The long period of the stellar binary, ~3x10^4 yr, implies that less than 1% of the orbit has transpired since its first astrometric measurements in 1830. …
The Dusty Starburst Nucleus of M33
Gordon, Karl D.; Rieke, G. H.; Clayton, Geoffrey C. +2 more
We have thoroughly characterized the ultraviolet to near-infrared (0.15-2.2 µm) spectral energy distribution (SED) of the central parsec of the M33 nucleus through new infrared photometry and optical/near-infrared spectroscopy, combined with ultraviolet/optical observations from the literature and the Hubble Space Telescope archive. The SED …
A Highly Collimated Bipolar Outflow in a Proto-planetary Nebula: Hubble Space Telescope Imaging of HEN 401
Bujarrabal, V.; Sahai, Raghvendra; Zijlstra, A.
We have obtained high-resolution wide- and narrowband images of the bipolar proto-planetary nebula Hen 401 with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. Two very long (14.5"), cylindrical-shaped bipolar outflow lobes are seen in reflected light, each with a length/width ratio of ~7, probably the largest seen in a prot…
Hubble Space Telescope Observations of the Optical Jets of PKS 0521-365, 3C 371, and PKS 2201+044
Urry, C. Megan; Scarpa, Riccardo; Treves, Aldo +1 more
Hubble Space Telescope (HST) observations have led to the discovery of the optical counterpart of the radio jet of PKS 2201+044 and to a detailed analysis of the optical jets of PKS 0521-365 and 3C 371. At HST spatial resolution these jets are well resolved, displaying knotty morphologies. When compared with radio maps of appropriate resolution, a…
The metal-rich globular clusters of the Milky Way
Richtler, T.; Heitsch, F.
We present new (V,V-I)-photometry of the metal-rich globular clusters
The Hubble Space Telescope Survey of BL Lacertae Objects: Gravitational Lens Candidates and Other Unusual Sources
Urry, C. Megan; O'Dowd, Matthew; Scarpa, Riccardo +4 more
We present Hubble Space Telescope (HST) observations of seven unusual objects from the HST ``snapshot survey'' of BL Lacertae objects, of which four are gravitational lens candidates. In three cases a double point source is observed: 0033+595, with 1.58" separation, and 0502+675 and 1440+122, each with ~0.3" separation. The last two also show one …
Classification of EUV stellar sources detected by the ROSAT WFC. I. Photometric and radial velocity studies
Tagliaferri, G.; Pallavicini, R.; Messina, S. +2 more
We present the results of high-precision UBV(RI)_c photometric observations and of spectroscopic radial velocity measurements obtained at the European Southern Observatory for a sample of 51 cool stars detected in the EUV by the ROSAT Wide Field Camera (WFC). Using also recent results from HIPPARCOS, we infer spectral types and investigate the sin…