Search Publications
Warm gas in the cold diffuse interstellar medium: Spectral signatures in the H2 pure rotational lines
Falgarone, E.; Hily-Blant, P.; Pineau Des Forêts, G. +1 more
We present ISO-SWS observations of five pure rotational lines of H2 along a line of sight through the Galaxy which avoids regions of massive star formation. It samples 30 mag of gas, half of it (i.e. 15 mag) being diffuse gas running from the solar neighbourhood to the molecular ring, up to the far side of the Galaxy. The intensities of…
The radio-ultraviolet spectral energy distribution of the jet in 3C 273
Meisenheimer, K.; Jester, S.; Röser, H. -J. +1 more
We present deep VLA and HST observations of the large-scale jet in 3C 273 matched to 0.3 arcsec resolution. The observed spectra show a significant flattening in the infrared-ultraviolet wavelength range. The jet's emission cannot therefore be assumed to arise from a single electron population and requires the presence of an additional emission co…
VLT narrow-band photometry in the Lyman continuum of two galaxies at z ∼3. Limits to the escape of ionizing flux
Buat, V.; Burgarella, D.; Inoue, A. K. +2 more
We have performed narrow-band imaging observations with the Very Large Telescope, aimed at detecting the Lyman continuum (LC) flux escaping from galaxies at z∼3. We do not find any significant LC flux from our sample of two galaxies in the Hubble Deep Field South, at z=3.170 and 3.275. The corresponding lower limits on the F1400/F9…
INTEGRAL observations of SS433: Results of a coordinated campaign
Bikmaev, I. F.; Sunyaev, R. A.; Sakhibullin, N. A. +18 more
Results of simultaneous INTEGRAL and optical observations of the galactic microquasar SS433 in May 2003 and INTEGRAL /RXTE observations in March 2004 are presented. Persistent precessional variability with a maximum to minimum uneclipsed hard X-ray flux ratio of ∼ 4 is discovered. The 18 60 keV X-ray eclipse is found to be in phase with optical an…
A substellar companion around the intermediate-mass giant star HD 11977
Pasquini, L.; de Medeiros, J. R.; Hatzes, A. P. +6 more
We report the discovery of a substellar companion to the intermediate-mass star
XMM-Newton observations of the Lockman Hole. III. A relativistic Fe line in the mean X-ray spectra of type-1 and type-2 AGN
Finoguenov, A.; Streblyanska, A.; Barcons, X. +3 more
Using the 770 ks XMM-Newton survey of the Lockman Hole field in combination with extensive optical identifications of the AGN population, we derive an average rest-frame spectrum of AGN types-1 and 2. The most prominent feature in the averaged spectrum is a strong fluorescent Fe line. In both type-1 and type-2 AGN, a clear relativistic line profil…
HST/ACS Lyman α imaging of the nearby starburst ESO 338-IG04
Östlin, G.; Hayes, M.; Mas-Hesse, J. M. +3 more
ESO 338-IG04 (Tololo 1924-416) is a well-known, luminous (MV = -19.3) Blue Compact Galaxy in the local universe. Its complex morphology indicates a recent merger and/or close interaction, and it contains a central young starburst with compact star clusters of ages ≲ 40 Myr. The galaxy was imaged using the Advanced Camera for Surveys onb…
Oxygen-rich AGB stars with optically thin dust envelopes
Heras, A. M.; Hony, S.
The dust composition and dynamics of the circumstellar envelopes of oxygen-rich AGB stars with low mass-loss rates (5 × 10-8-10-5 M⊙ yr-1) have been investigated. We have analyzed the ISO-SWS spectra of twenty-eight oxygen-rich AGB stars with optically thin shells, and modelled the observations with the …
Thick disks and halos of spiral galaxies M 81, NGC 55 and NGC 300
Tikhonov, N. A.; Galazutdinova, O. A.; Drozdovsky, I. O.
By using images from the HST/WFPC2/ACS archive, we have analyzed the spatial distribution of the AGB and RGB stars along the galactocentric radius of nearby spiral galaxies M 81, NGC 300 and NGC 55. Examining color-magnitude diagrams and stellar luminosity functions, we gauge the stellar contents of the surroundings of the three galaxies. The red …
Integral field spectroscopy of the ultraluminous X-ray source Holmberg II X-1
Greiner, J.; Costantini, E.; Roth, M. +10 more
We present optical integral field observations of the H II region containing the ultraluminous X-ray source Holmberg II X-1. We confirm the existence of an X-ray ionized nebula as the counterpart of the source owing to the detection of an extended He II λ4686 region (21× 47 pc) at the Chandra ACIS-S position. An extended blue object with a size of…