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Chandra and Hubble Space Telescope Confirmation of the Luminous and Variable X-Ray Source IC 10 X-1 as a Possible Wolf-Rayet, Black Hole Binary
Brandt, W. N.; Bauer, Franz E.
We present a Chandra and Hubble Space Telescope study of IC 10 X-1, the most luminous X-ray binary in the starburst galaxy closest to the Milky Way. Our new hard X-ray observation of X-1 confirms that it has an average 0.5-10 keV luminosity of 1.5×1038 ergs s-1, is strongly variable (a factor of ~2 in <~3 ks), and is spati…
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…
Photometry of Magellanic Cloud clusters with the Advanced Camera for Surveys - I. The old Large Magellanic Cloud clusters NGC 1928, 1939 and Reticulum
Mackey, A. D.; Gilmore, G. F.
We present the results of photometric measurements from images of the Large Magellanic Cloud (LMC) globular clusters NGC 1928, 1939 and Reticulum taken with the Advanced Camera for Surveys on the Hubble Space Telescope. Exposures through the F555W and F814W filters result in high-accuracy colour-magnitude diagrams (CMDs) for these three clusters. …
Energy-flux relationship in the FUV Jovian aurora deduced from HST-STIS spectral observations
Clarke, J. T.; Cowley, S. W. H.; Grodent, D. +3 more
Far ultraviolet spectral observations of the Jovian aurora have been made since 1997 with the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope at low spectral resolution. The combination of the spectral resolution with the intensity variation along the STIS slit provides information on the latitudinal variation of th…
A possible auroral signature of a magnetotail reconnection process on Jupiter
Clarke, J. T.; Waite, J. H.; Grodent, D. +2 more
Several theoretical models and in situ observations consistently suggest that the process of nightside reconnection associated with Earth's magnetospheric substorms is also taking place in the midnight tail region of Jupiter. We report the observation of a new auroral feature which takes the form of isolated spots appearing near the northern dusk-…
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…
Motions of Flare Ribbons and Loops in Various Magnetic Configurations
Lin, Jun
Kopp-Pneuman-type magnetic configurations, which include a vertical current sheet, with various background fields are investigated. Dissipation of the current sheet as a result of magnetic reconnection produces bright flare ribbons on the solar disk and a growing flare loop system in the corona. In principle, the growth of flare loop system is gov…
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