Search Publications
Global physical conditions of the interstellar medium in nearby galaxies
Onaka, T.; Roellig, T. L.; Negishi, T. +1 more
Far-infrared spectra (43-197 mu m) of 34 nearby galaxies obtained by the Long Wavelength Spectrometer (LWS) aboard the Infrared Space Observatory (ISO) were analyzed to investigate the general properties of interstellar matter in galaxies. The present sample includes not only normal galaxies but also starbursts and active galactic nuclei (AGNs). F…
The XMM-Newton view of stellar coronae: Coronal structure in the Castor X-ray triplet
Mewe, R.; Audard, M.; Güdel, M. +5 more
We present results of a comprehensive X-ray investigation of the multiple stellar system
Warm H2 in the Galactic center region
Rodríguez-Fernández, N. J.; Martín-Pintado, J.; Fuente, A. +3 more
We present ISO observations of several H2 pure-rotational lines (from S(0) to S(5)) towards a sample of 16 molecular clouds distributed along the central ~ 500 pc of the Galaxy. We also present C18 O and {13 CO J=1->0 and J=2 -> 1 observations of these sources made with the IRAM-30 m telescope. With the CO da…
Asymmetries in the HD 141569 circumstellar disk
Ménard, F.; Mouillet, D.; Augereau, J. C. +1 more
We present HST/STIS coronagraphic observations of the disk around HD 141569. The data, with a spatial resolution and signal to noise higher than those previously obtained with HST/NICMOS2 allow a more detailed insight in the system. They reveal a very structured system, in which two ring-like structures at distances =~ 200 and 325 AU from the star…
Kinematics of young stars. II. Galactic spiral structure
Figueras, F.; Torra, J.; Fernández, D.
The young star velocity field is analysed by means of a galactic model which takes into account solar motion, differential galactic rotation and spiral arm kinematics. We use two samples of Hipparcos data, one containing O- and B-type stars and another one composed of Cepheid variable stars. The robustness of our method is tested through careful k…
Crystallinity versus mass-loss rate in asymptotic giant branch stars
Waters, L. B. F. M.; de Koter, A.; Tielens, A. G. G. M. +1 more
Infrared Space Observatory (ISO) observations have shown that O-rich Asymptotic Giant Branch (AGB) stars exhibit crystalline silicate features in their spectra only if their mass-loss rate is higher than a certain threshold value. Usually, this is interpreted as evidence that crystalline silicates are not present in the dust shells of low mass-los…
Dust in the Tycho, Kepler and Crab supernova remnants
Dwek, E.; Lagage, P. O.; Cesarsky, C. J. +1 more
SuperNova Remnants (SNR) have been extensively studied in radio, X-rays and optical, but barely in the InfraRed (IR). From IRAS observations, SNR are known to be IR emitters, but the origin of the emission is difficult to assess because of the limited angular and spectral resolution of IRAS observations. ISO follow-up observations of the Cassiopei…
The central region of M 31 observed with XMM-Newton. II. Variability of the individual sources
Pietsch, W.; Read, A. M.; Tiengo, A. +13 more
We present the results of a study of the variability of X-ray sources in the central 30 arcmin of the nearby Andromeda Galaxy (M 31) based on XMM-Newton Performance Verification observations. Two observations of this field, with a total exposure time of about 50 ks, were performed in June and December of 2000. We found 116 sources brighter than a …
The central region of M 31 observed with XMM-Newton. I. Group properties and diffuse emission
Pietsch, W.; Read, A. M.; Tiengo, A. +13 more
We present the results of a study based on an XMM-Newton Performance Verification observation of the central 30' of the nearby spiral galaxy M 31. In the 34-ks European Photon Imaging Camera (EPIC) exposure, we detect 116 sources down to a limiting luminosity of 6 x 1035 erg s-1 (0.3-12 keV, d=760 kpc). The luminosity distrib…
The plerion nebula in IC 443: The XMM-Newton view
Bocchino, F.; Bykov, A. M.
XMM-Newton observations of the X-ray feature 1SAX J0617.1+2221 in the IC 443 supernova remnant are reported. We resolve the structure of the nebula into a compact core with a hard spectrum of photon index gamma = 1.63+0.11-0.10 in the 2-10 keV energy range. The nebula also has an extended ({ ~ } 8hbox {^\prime}times 5arcmin )…