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Hubble Space Telescope Observations of the CfA Seyfert 2 Galaxies: Near-Infrared Surface Photometry and Nuclear Bars
Ravindranath, Swara; Pogge, Richard W.; Martini, Paul +1 more
We present near-infrared J and H surface photometry of 24 of the nearby Seyfert 1.8, 1.9, and 2 galaxies from the CfA Seyfert sample. The excellent angular resolution of the Hubble Space Telescope probes spatial scales as small as tens of parsecs in most of these active galactic nuclei (AGNs) and is sensitive to the presence of nuclear bars and ot…
Horizontal-Branch Models and the Second-Parameter Effect. IV. The Case of M3 and Palomar 3
Catelan, M.; Ferraro, F. R.; Rood, R. T.
We present a detailed analysis of the ``second-parameter pair'' of globular clusters M3 (NGC 5272) and Palomar 3. Our main results can be summarized as follows: (1) The horizontal-branch (HB) morphology of M3 is significantly bluer in its inner regions (observed with the Hubble Space Telescope) than in the cluster outskirts (observed from the grou…
Far Ultraviolet Spectroscopic Explorer Observations of Capella
Young, P. R.; Moos, H. W.; Linsky, J. L. +4 more
Far Ultraviolet Spectroscopic Explorer observations of the binary system Capella reveal a rich emission-line spectrum containing neutral and ionic species, among them H I, O I, C III, O VI, S VI, Ne V, and Ne VI. In addition, Fe XVIII λ974.85, formed at temperatures of ~6×106 K, is detected. Whereas the strong transition region lines pr…
Multiwavelength Study of the Starburst Galaxy NGC 7714. II. The Balance between Young, Intermediate-Age, and Old Stars
Leitherer, Claus; Lançon, Ariane; González Delgado, Rosa M. +1 more
We combine existing multiwavelength data (including an HST/GHRS UV spectrum and a ground-based optical spectrum) with unpublished HST/WFPC2 images, near-IR photometry, and K-band spectroscopy. We use these data to constrain the young, the intermediate-age, and the old stellar populations in the central regions of the starburst galaxy NGC 7714. In …
Ultraviolet Spectropolarimetry of Narrow-Line Radio Galaxies
Dey, Arjun; Spinrad, Hyron; van Breugel, Wil +4 more
We present the results of UV spectropolarimetry (λrest~=2000-3000 Å) and far-UV spectroscopy (λrest~=1500-2000 Å) of two low-redshift narrow-line radio galaxies (NLRGs) taken with the Faint Object Spectrograph on board the Hubble Space Telescope (HST). Spectropolarimetry of several NLRGs has shown that, by the presence of bro…
On the Nature of Intrinsic Absorption in Reddened Seyfert 1 Galaxies
Kraemer, S. B.; Crenshaw, D. M.
We discuss the origin of the ``dusty lukewarm absorber,'' which we previously identified in the reddened Seyfert 1 galaxies NGC 3227 and Akn 564. This absorber is characterized by saturated UV absorption lines (C IV, N V) near the systemic velocity of the host galaxy and is likely responsible for reddening both the continuum and emission lines (in…
Atomic Oxygen Abundance in Molecular Clouds: Absorption toward Sagittarius B2
Schilke, P.; Lis, D. C.; Phillips, T. G. +3 more
We have obtained high-resolution (~35 km s-1) spectra toward the molecular cloud Sgr B2 at 63 µm, the wavelength of the ground-state fine-structure line of atomic oxygen (O I), using the ISO-LWS instrument. Four separate velocity components are seen in the deconvolved spectrum, in absorption against the dust continuum emission of …
The Type IC SN 1990B in NGC 4568
Dickinson, Mark; Filippenko, Alexei V.; Shields, Joseph C. +25 more
We present a study of the Type Ic supernova (SN) 1990B that includes most of the observations obtained from around the world. The combined data set comprises 84 BV(RI)c photometric points spanning approximately 360 days after maximum light and 14 spectra from 5 up to ~150 days after maximum light. In contrast to other Type Ic SNe, SN 19…
Phase-resolved Hubble Space Telescope/STIS Spectroscopy of the Exposed White Dwarf in the High-Field Polar AR Ursae Majoris
Szkody, Paula; Gänsicke, Boris T.; Jordan, Stefan +1 more
Phase-resolved Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) ultraviolet spectroscopy of the high-field polar AR UMa confirms that the white dwarf photospheric Lyα Zeeman features are formed in a magnetic field of ~200 MG. In addition to the Lyα π and σ+ components, we detect the forbidden hydrogen 1s0
Infrared and Millimetric Study of the Young Outflow Cepheus E
Cernicharo, José; Testi, Leonardo; Molinari, Sergio +3 more
The Cepheus E outflow has been studied in the mid- and far-IR using the ISOCAM and Long Wavelength Spectrometer (LWS) instruments and at millimetric wavelengths using the Owens Valley Radio Observatory (OVRO). In the near- and mid-IR, its morphology is similar to that expected for a jet-driven outflow, where the leading bow shocks entrain and acce…