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Cassiopeia A dust composition and heating
Pantin, E.; Lagage, P. O.; Douvion, T.
Material ejected by a supernova is directly observed in the form of Fast Moving Knots (FMK's) in the Cassiopeia A supernova remnant. Part of this material has condensed into dust. In this paper, by fitting the ISO mid-infrared emission of the dust, we derive the dust composition and discuss the dust heating. The dust is found to be made mainly of …
Wind circulation in selected rotating magnetic early-B stars
Smith, M. A.; Groote, D.
The rotating magnetic B stars are a class of variables consisting of He-strong and some beta Cep stars which have oblique dipolar magnetic fields. Such stars develop co-rotating, torus-shaped clouds by channeling wind particles from their magnetic poles to circumstellar regions centered around the plane of their magnetic equators. The rotation of …
Reprocessing the Hipparcos data for evolved giant stars II. Absolute magnitudes for the R-type carbon stars
Jorissen, A.; Pourbaix, D.; Knapp, G.
The Hipparcos Intermediate Astrometric Data for carbon stars have been reprocessed using an algorithm which provides an objective criterion for rejecting anomalous data points and constrains the parallax to be positive. New parallax solutions have been derived for 317 cool carbon stars, mostly of types R and N. In this paper we discuss the results…
A Search for Signatures of Quasar Evolution: Comparison of the Shapes of the Rest-Frame Optical/Ultraviolet Continua of Quasars at z>3 and z~0.1
Elvis, Martin; Bechtold, Jill; Elston, Richard +1 more
For 15 bright (V<17.5), high-redshift (z>3) quasars, we have obtained infrared spectra and photometry, and optical spectrophotometry and photometry, which we use to construct their spectral energy distributions (SEDs) from λrest~1285-5100 Å. High-resolution spectroscopy for seven enable measurements of their continua shortward of …
Cluster magnetic field observations of the bowshock: Orientation, motion and structure
Balogh, A.; Horbury, T. S.; Lucek, E. A. +7 more
Four spacecraft Cluster magnetic field observations of the low <beta> quasi-perpendicular terrestrial bowshock are presented for the first time. Multiple quasi-perpendicular crossings on 25 December 2000 are analysed. By combining data from the four spacecraft, bowshock orientations and velocities can be calculated. It is shown that, even wh…
The X-Ray Afterglow of GRB 000926 Observed by BeppoSAX and Chandra: A Mildly Collimated Fireball in a Dense Medium?
Piro, L.; Antonelli, L. A.; Frail, D. A. +8 more
We present X-ray observations of the afterglow of GRB 000926, performed around and after the break observed in the optical light curve 2 days after the burst. The steep X-ray light curve observed around the break confirms the presence of this feature in X-rays. However, the spectral and temporal properties are not consistent with a standard jet sc…
Infrared spectrum and proper motion of the brown dwarf companion of HR 7329 in Tucanae
Neuhäuser, R.; Guenther, E. W.; Huélamo, N. +2 more
Up to now only four brown dwarf companions to normal stars have been found and confirmed by both spectroscopy and proper motion (namely
Broadband infrared photometry of comet Hale-Bopp with ISOPHOT
Krüger, H.; Lamy, P.; Keller, H. U. +21 more
Comet Hale-Bopp was observed five times with ISOPHOT, the photometer on board ESA's Infrared Space Observatory (ISO) between 4.6 and 2.8 AU. Each time, broadband photometry was performed using 4 different detectors, 5 apertures and 10 filters covering the range between 3.6 and 170 mu m. Background observations were performed with identical instrum…
Water in K and M giant stars unveiled by ISO
Tsuji, T.
Based on the spectra obtained with Infrared Space Observatory, ISO, we detected the 6.3 mu m bands of water in the late K giant Aldebaran (alpha Tau) and several early M giant stars (between M0 and M3.5), which have been deemed to be too warm for tri-atomic H2O molecule to reside in their photospheres. The water column densities range (…
SCUBA photometry of candidate Vega-like sources
Barlow, M. J.; Sylvester, R. J.; Dunkin, S. K.
New SCUBA measurements at millimetre wavelengths are presented for a sample of Vega-like stars. Six stars were detected, while sensitive upper limits were obtained for a further 11 sources. Most of the sample selected from a recent catalogue of Vega-like stars have infrared excesses similar to those of the prototype Vega-like stars α Lyr and α PsA…