Search Publications
Discovery of X-ray emission from the protostellar jet L1551 IRS5 (HH 154)
Micela, G.; Favata, F.; Sciortino, S. +2 more
We have for the first time detected X-ray emission associated with a protostellar jet, on the jet emanating from the L1551 IRS5 protostar. The IRS5 protostar is hidden behind a very large absorbing column density, making the direct observation of the jet's emission possible. The observed X-ray emission is likely associated with the shock ``working…
Dust and the spectral energy distribution of the OH/IR star OH 127.8+0.0: Evidence for circumstellar metallic iron
Waters, L. B. F. M.; de Koter, A.; Tielens, A. G. G. M. +2 more
We present a fit to the spectral energy distribution of
Nanodiamonds around HD 97048 and Elias 1
Tielens, A. G. G. M.; Waelkens, C.; Van Kerckhoven, C.
We present an analysis of ISO-SWS observations of the Herbig Ae/Be stars HD 97048 and Elias 1. Besides the well-known family of IR emission bands at 3.3, 6.2, ``7.7'', 8.6 and 11.2 mu m these objects show strong, peculiar emission features at 3.43 and 3.53 mu m. The latter two features show pronounced substructure which is very similar in the two …
The origin of the young stellar population in the solar neighborhood -- A link to the formation of the Local Bubble?
Breitschwerdt, D.; Berghöfer, T. W.
We have analyzed the trajectories of moving stellar groups in the solar neighborhood in an attempt to estimate the number of supernova explosions in our local environment during the past 20 million years. Using Hipparcos stellar distances and the results of kinematical analyses by Asiain et al. (\cite{Asiain1999a}a) on the Pleiades moving groups, …
An optical time-delay for the lensed BAL quasar HE 2149-2745
Kneib, J. -P.; Magain, P.; Lidman, C. +11 more
We present optical V and i-band light curves of the gravitationally lensed BAL quasar HE 2149-2745. The data, obtained with the 1.5 m Danish Telescope (ESO-La Silla) between October 1998 and December 2000, are the first from a long-term project aimed at monitoring selected lensed quasars in the Southern Hemisphere. A time delay of 103+/-12 days is…
The magnetic nature of wide EUV filament channels and their role in the mass loading of CMEs
Aulanier, G.; Schmieder, B.
Previous works have shown that dark and wide EUV filament channels observed at lambda < 912 Å, are due to absorption of EUV lines in cool plasma condensations that are not observed in Hα . We extend this interpretation and we address the issue of the possible injection of their mass into CMEs, through the magneto-hydrostatic modeling in 3D of o…
UVCS/SOHO observations of a CME-driven shock: Consequences on ion heating mechanisms behind a coronal shock
Raymond, J. C.; Wu, R.; Kohl, J. +3 more
We report the observation of a 1100 km s-1 CME-driven shock with the UltraViolet Coronagraph Spectrometer (UVCS) telescope operating on board SOHO on March 3, 2000. The shock speed was derived from the type II radio burst drift rate and from UVCS observations that can yield the density profile just before the passage of the shock. A CME…
Multi-wavelength study of the Seyfert 1 galaxy NGC 3783 with XMM-Newton
Kaastra, J. S.; Behar, E.; Sako, M. +5 more
We present the analysis of multi-wavelength XMM-Newton data from the Seyfert galaxy NGC 3783, including UV imaging, X-ray and UV lightcurves, the 0.2-10 keV X-ray continuum, the iron Kalpha emission line, and high-resolution spectroscopy and modelling of the soft X-ray warm absorber. The 0.2-10 keV spectral continuum can be well reproduced by a po…
Shock-excited radio burst from reconnection outflow jet?
Mann, G.; Vršnak, B.; Aurass, H.
Models of dynamic (two-ribbon-, arcade) flares involve the formation of a system of standing slow and possibly also fast mode shock waves associated with the fast reconnection process below the erupting filament. These shocks are anticipated theoretically, but are not unambiguously confirmed by observations. In this paper we identify for the first…
Hidden star-formation in the cluster of galaxies Abell 1689
Elbaz, D.; Cesarsky, C.; Duc, P. -A. +6 more
At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75 micron (LW2 filter) and 16 cluster members at 15 micron (LW3 filter) within a clustercen…