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HST images of B2 radio galaxies: A link between circum-nuclear dust and radio properties?
Capetti, A.; Morganti, R.; de Ruiter, H. R. +2 more
Almost 60% of the B2 low luminosity radio galaxies have been observed with the Hubble Space Telescope. We present an analysis of the dust features, which are often present in the form of circum-nuclear disks or lanes, and show that there are correlations between radio source and dust properties. It is found that nearby radio sources in which a jet…
XMM-Newton Reflection Grating Spectrometer observations of the prototypical starburst galaxy M82
Stevens, Ian R.; Read, Andrew M.
We present results from XMM-Newton Reflection Grating Spectrometer observations of the prototypical starburst galaxy M82. These high-resolution spectra represent the best X-ray spectra to date of a starburst galaxy. A complex array of lines from species over a wide range of temperatures is seen, the most prominent being due to Lyman α emission fro…
Near-Infrared Adaptive Optics Imaging of the Central Regions of Nearby Sc Galaxies. II. NGC 247 and NGC 2403
Davidge, T. J.; Courteau, S.
J, H, and K' images obtained with the Canada-France-Hawaii Telescope adaptive optics system are used to investigate the star-forming histories of the central regions of the Sc galaxies NGC 247 and NGC 2403. The brightest resolved red stars within 15" of the nucleus of each galaxy are red supergiants (RSGs), indicating that the central few hundred …
A New Infrared Band in Interstellar and Circumstellar Clouds: C4 or C4H?
Cernicharo, José; Goicoechea, Javier R.; Benilan, Yves
We report on the detection with the Infrared Space Observatory of a molecular band at 57.5 µm (174 cm-1) in carbon-rich evolved stars and in Sgr B2. Taking into account the chemistry of these objects, the most likelihood carrier is a carbon chain. We tentatively assign the band to the ν5 bending mode of C4 fo…
Complex X-Ray Spectral Variability in Markarian 421 Observed with XMM-Newton
Edelson, R.; Turner, M. J. L.; Markowitz, A. +2 more
The bright blazar Mrk 421 has been observed four times for uninterrupted durations of ~9-13 hr during the performance verification and calibration phases of the XMM-Newton mission. The source was strongly variable in all epochs, with variability amplitudes that generally increased to higher energy bands. Although the detailed relationship between …
Gas Kinematics and the Black Hole Mass at the Center of the Radio Galaxy NGC 4335
Baum, Stefi A.; van der Marel, Roeland P.; de Zeeuw, P. Tim +2 more
We investigate the kinematics of the central gas disk of the radio-loud elliptical galaxy NGC 4335, derived from Hubble Space Telescope (HST) long-slit spectroscopic observations of Hα+[N II] along three parallel slit positions. The observed mean velocities are consistent with a rotating thin disk. We model the gas disk in the customary way, takin…
Hot dust in normal star-forming galaxies: JHKL' photometry of the ISO Key Project sample
Helou, G.; Hunt, L. K.; Giovanardi, C.
We present JHK and 3.8 mu m (L') photometry of 26 galaxies in the Infrared Space Observatory (ISO) Normal Galaxy Key Project (KP) sample and of seven normal ellipticals with the aim of investigating the origin of the 4 mu m emission. The majority of the KP galaxies, and all the ellipticals, have K-L<~ 1.0, consistent with stellar photospheres p…
The Alpha Magnetic Spectrometer (AMS)
Usoskin, I.; Laitinen, T.; Valtonen, E. +199 more
The Alpha Magnetic Spectrometer (AMS) is a large acceptance ( 0.65 sr m 2) detector designed to operate in the International Space Station (ISS) for three years. The purposes of the experiment are to search for cosmic antimatter and dark matter and to study the composition and energy spectrum of the primary cosmic rays. A "scaled-down" …
Elemental Abundances and Ionization States within the Local Interstellar Cloud Derived from Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer Observations of the Capella Line of Sight
Redfield, Seth; Wood, Brian E.; Linsky, Jeffrey L. +1 more
We use ultraviolet spectra of Capella from the Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer satellites to study interstellar absorption lines from the Local Interstellar Cloud (LIC). Measurements of these lines are used to empirically determine the ionization states of carbon, nitrogen, and silicon in the LIC, for comparison w…
An Infrared Space Observatory Atlas of Bright Spiral Galaxies
Bendo, George J.; Leech, Kieron; Metcalfe, Leo +11 more
In this first paper in a series we present an atlas of infrared images and photometry from 1.2 to 180 µm for a sample of bright spiral galaxies. The atlas galaxies are an optically selected, magnitude-limited sample of 77 spiral and S0 galaxies chosen from the Revised Shapley-Ames Catalog (RSA). The sample is a representative sample of spira…