Search Publications
Physical Properties of the X-Ray-Luminous SN 1978K in NGC 1313 from Multiwavelength Observations
Staveley-Smith, L.; Schlegel, Eric M.; Dopita, M. +4 more
We update the light curves from the X-ray, optical, and radio bandpasses which we have assembled over the past decade and present two observations in the ultraviolet using the Hubble Space Telescope Faint Object Spectrograph. The HRI X-ray light curve is constant within the errors over the entire observation period. This behavior is confirmed in t…
Multiwavelength Imaging and Long-Slit Spectroscopy of the Planetary Nebula NGC 6884: The Discovery of a Fast Precessing, Bipolar Collimated Outflow
Guerrero, Martín A.; Miranda, Luis F.; Torrelles, José M.
We present Hα, [N II] lambda6583, [O III] lambda5007 ground-based images, Hubble Space Telescope (HST) (V band) archival images, VLA-A 3.6 cm continuum data, and high-resolution long-slit spectra of the planetary nebula NGC 6884. The VLA and HST images show an extremely knotty and filamentary nebula with an elliptical central structure also recogn…
High-Resolution Millimeter and Infrared Observations of the Hot Spots of Cygnus A
Miley, G. K.; Carilli, C. L.; Kurk, J. D. +2 more
We present high-resolution, polarimetric imaging of the radio hot spots of Cygnus A at 7 mm with the Very Large Array and derive limits to hot spot emission at 12 µm with the Infrared Space Observatory (ISO). The 7 mm images reveal the hot spot structure in total and polarized intensity in unprecedented detail, including images of the projec…
New HST Observations of the Halo Gas of NGC 3067: Limits on the Extragalactic Ionizing Background at Low Redshift and the Lyman Continuum Escape Fraction
Shull, J. Michael; Stocke, John T.; Tumlinson, Jason +1 more
We present ultraviolet spectroscopy from HST/GHRS and reanalyze existing Hα images of the quasar/galaxy pair 3C 232/NGC 3067 and of the halo gas associated with NGC 3067. The spectra permit measurement of, or limits on, the column densities of Fe I, Fe II, Mg I, and Mg II in the absorbing cloud. Two distinct models of the extragalactic radiation f…
Stellar Kinematics of the Double Nucleus of M31
King, Ivan R.; Statler, Thomas S.; Crane, Philippe +1 more
We report observations of the double nucleus of M31 with the f/48 long-slit spectrograph of the Hubble Space Telescope Faint Object Camera. We obtain a total exposure of 19,000 s over seven orbits, with the 0.063"-wide slit along the line between the two brightness peaks (P.A. 42 deg). Careful correction of the raw data for detector backgrounds an…
Mapping the Variegated Surface of Pluto
Buie, Marc W.; Tholen, David J.; Young, Eliot F. +2 more
During the period from 1985 through 1990, Pluto and its satellite Charon underwent a series of transits, eclipses, and occultations, which are collectively called ``mutual events.'' The albedo distribution of Pluto's sub-Charon hemisphere can be determined from these events with a spatial resolution that surpasses any current direct-imaging scheme…
Determining the Galactic Mass Distribution Using Tidal Streams from Globular Clusters
Murali, Chigurupati; Dubinski, John
We discuss how to use tidal streams from globular clusters to measure the mass distribution of the Milky Way. Recent proper-motion determinations for globular clusters from plate measurements and Hipparcos astrometry provide several good candidates for Galactic mass determinations in the intermediate halo far above the Galactic disk, including Pal…
Young Stellar Nuclei in the Lenticular Galaxies. I. NGC 1023 and NGC 7332
Sil'chenko, O. K.
As a result of bidimensional spectroscopy of the central parts of two nearby lenticular galaxies, NGC 1023 and NGC 7332, undertaken with the Multi-Pupil Field Spectrograph of the 6 m telescope of the Special Astrophysical Observatory, their chemically decoupled stellar nuclei are found to be substantially younger than the surrounding bulges: the m…
A Hubble Space Telescope Optical and Ground-based Near-Infrared Study of the Giant Nuclear Ring in ESO 565-11
Buta, R.; Crocker, D. A.; Byrd, G. G.
We present multiband Wide Field Planetary Camera 2 images of the central regions of ESO 565-11, a peculiar southern barred galaxy recently shown to have the largest known example of a circumnuclear starburst ring. We also present ground-based near-infrared H-band imaging and photometry of the galaxy. The results provide an interesting picture of t…
Radio Detections of Stellar Winds from the Pistol Star and Other Stars in the Galactic Center Quintuplet Cluster
Goss, W. M.; Morris, Mark; Lang, Cornelia C. +1 more
Very Large Array images of the Sickle and Pistol H II regions near the Galactic center at 8.3 and 4.9 GHz reveal six point sources in the region where the dense Quintuplet stellar cluster is located. The spectral indices of five of these sources between 6 and 3.6 cm have values of α=0.5 to 0.8 (where Sν~να), consistent with t…