Search Publications
Emission of CO, C I, and C II in W3 Main
Schneider, N.; Stutzki, J.; Kramer, C. +3 more
We used the KOSMA 3m telescope to map the core 7' × 5' of the Galactic massive star forming region W3 Main in the two fine structure lines of atomic carbon and four mid-J transitions of CO and 13CO. The maps are centered on the luminous infrared source IRS 5 for which we obtained ISO/LWS data comprising four high-J CO transitions, [C II…
Mid-IR observations of Galactic H II regions: Constraining ionizing spectra of massive stars and the nature of the observed excitation sequences
Morisset, C.; Schaerer, D.; Bouret, J. -C. +1 more
Extensive photoionization model grids for single star H II regions using state-of-the-art stellar atmosphere models have been computed to test their predicted ionizing spectra against recent ISO mid-IR observations of Galactic H II regions. Particular care has been paid to examining in detail the dependences of the nebular properties on the numero…
The Small Magellanic Cloud in the far infrared. II. Global properties
Lemke, D.; Klaas, U.; Haas, M. +3 more
We present global IR properties of the Small Magellanic Cloud using an ISOPHOT 170 µm map and re-visited IRAS data. The integrated 170 µm flux is 14 950 ± 2300 Jy, and the integrated IR flux is F1-1000 = 7.48 × 10-10 W m-2. Discrete sources contribute 28%, 29%, and 36% to the integrated flux at 60 &micr…
Discovery of optically faint obscured quasars with Virtual Observatory tools
Rosati, P.; Walton, N. A.; Padovani, P. +1 more
We use Virtual Observatory (VO) tools to identify optically faint, obscured (i.e., type 2) active galactic nuclei (AGN) in the two Great Observatories Origins Deep Survey (GOODS) fields. By employing publicly available X-ray and optical data and catalogues we discover 68 type 2 AGN candidates. The X-ray powers of these sources are estimated by usi…
Diffraction-limited bispectrum speckle interferometry of the nuclear region of the Seyfert galaxy NGC 1068 in the H and K' bands
Duschl, W. J.; Weigelt, G.; Hofmann, K. -H. +5 more
We present near-infrared bispectrum speckle interferometry studies of the nuclear region of the Seyfert 2 galaxy
Molecular gas in NUclei of GAlaxies (NUGA). II. The ringed LINER NGC 7217
Tacconi, L. J.; Hunt, L. K.; Schinnerer, E. +8 more
We present CO(1-0) and CO(2-1) maps of the LINER galaxy NGC 7217, obtained with the IRAM interferometer, at 2.4 arcsec×1.9 arcsec and 1.2 arcsec×0.8 arcsec resolution respectively. The nuclear ring (at r=12 arcsec=0.8 kpc) dominates the CO maps, and has a remarkable sharp surface density gradient at its inner edge. The latter is the site of the st…
A thorough study of the intriguing X-ray emission from the Cartwheel ring
Wolter, A.; Trinchieri, G.
We present the results from the high resolution Chandra observation of the
Coronal versus photospheric abundances of stars with different activity levels
Sanz-Forcada, J.; Micela, G.; Favata, F.
We report a detailed analysis of the coronal abundance of 4 stars with varying levels of activity and with accurately known photospheric abundances. The coronal abundance is determined here using a line flux analysis and a full determination of the differential emission measure. Photospheric abundance values are taken from the literature. Previous…
The young pulsar PSR B0540-69.3 and its synchrotron nebula in the optical and X-rays
Sollerman, J.; Lundqvist, P.; Shibanov, Yu. A. +1 more
The young PSR B0540-69.3 in the LMC is the only pulsar (except the Crab pulsar) for which a near-UV spectrum has been obtained. However, the absolute flux and spectral index of the HST/FOS spectrum are significantly higher than suggested by previous broad-band time-resolved groundbased UBVRI photometry. To investigate this difference, observations…
Multiband modelling of the Sun as a variable star from VIRGO/SoHO data
Pagano, I.; Lanza, A. F.; Rodonò, M.
The time series of total solar irradiance (TSI) and optical spectral irradiance at 402, 500 and 862 nm (SSIs) obtained by the VIRGO experiment on board the satellite SoHO are analysed in order to model their variability in the framework of a purely stellar-like approach. The different time scales of variability are estimated by means of the pooled…