Search Publications
Early-Type Galaxies in the Hubble Deep Field: The <mu_e>-r_e Relation and the Lack of Large Galaxies at High Redshift
Fasano, Giovanni; Cristiani, Stefano; Arnouts, Stephane +1 more
We present the results of detailed surface photometry of a sample of early-type galaxies in the Hubble Deep Field (HDF). Effective radii, surface brightnesses, and total V_606 magnitudes have been obtained, as well as U_300, B_450, I_814, J, H, and K colors, which are compared with the predictions of chemical spectrophotometric models of populatio…
Hubble Space Telescope Wide Field Planetary Camera 2 Observations of the Young Bipolar H II Region S106
Bally, John; Zinnecker, Hans; Rayner, John +1 more
We present narrowband Hubble Space Telescope Wide Field Planetary Camera 2 images of the bipolar H ii region S106 in the Hα line. The high-resolution images show unprecedented detail in the two nebular lobes, including prominent scalloped structure of the emission at the ionization front. The illuminating source of the nebula, S106 IR, is detected…
Ultraviolet Spectroscopy of AB Doradus with the Hubble Space Telescope: Impulsive Flares and Bimodal Profiles of C IV lambda1549 in a Young Star
Collier Cameron, A.; Huovelin, J.; Hakala, P. +3 more
We observed AB Doradus, a young and active late-type star (K0-K2 IV-V, P = 0.514 days), with the Goddard High Resolution Spectrograph of the post-COSTAR Hubble Space Telescope with time and spectral resolutions of 27 s and 15 km s^-1, respectively (1994 November 14.08-14.30 UT). The wavelength band (1531-1565 Å) included the strong C iv doublet (1…
An Ultraviolet Spectral Atlas of 10 Lacertae Obtained with the Goddard High Resolution Spectrograph on the Hubble Space Telescope
Savage, B. D.; Ebbets, D. C.; Carpenter, K. G. +16 more
Observations of the narrow-lined O-type star 10 Lacertae taken with the Goddard High Resolution Spectrograph in 1992 November are presented. The spectra cover the wavelength range 1181-1777 Å with a resolution of 15 km s^-1 and signal-to-noise ratio greater than 100:1. Absorption lines arising in the interstellar medium, the photosphere, and the s…
Deep Optical Imaging of the Bright Seyfert Galaxy NGC 5548: A Long, Very Low Surface Brightness Tail
Glazebrook, Karl; Tyson, J. Anthony; Fischer, Philippe +9 more
Deep Hubble Space Telescope Wide Field Camera (WFC-1) imaging of a region 3.7‧ east of the V = 13 mag Seyfert galaxy NGC 5548 in the F555W and F785LP bands, and deep ground-based V and I imaging, show a new extended, blue, low surface brightness structure, apparently a remnant of a tidal interaction associated with NGC 5548. If this straight, low …
The Ages of Disturbed Field Elliptical Galaxies. II. Central Properties
Silva, David R.; Bothun, Gregory D.
The formation of elliptical galaxies via the merger of gas-rich disks has received considerable attention in recent years, with many studies strongly supporting the merger hypothesis. When investigated in detail, the dynamics of a major merger that produces a high phase-space density of material (e.g., the center of an elliptical galaxy) invariabl…
Deep Spectroscopy in the Field of 3C 212
Stockton, Alan; Ridgway, Susan E.
We present the results of long-slit and multiaperture spectroscopy of faint galaxies in the field of the z = 1.049 quasar 3C 212. We show that an apparently aligned optical feature beyond the northwest radio lobe has a redshift z = 0.928, and a similarly aligned feature just beyond the southeast radio lobe has a redshift z = 1.053, quite close to …
Radio Emission from Young Stellar Objects near LkHα 101
Stine, Peter C.; O'Neal, Douglas
We present results of a VLA 3.6 cm B-configuration study of a region around the Herbig Be star LkHα 101. We detect 16 sources down to 5 sigma (rms) thresholds of 0.25 mJy. Most of the sources are thought to be young stellar objects associated with the star formation region. Six of the objects have optical counterparts, and at least two are weak-li…
An Empirical Limit on Extremely High Redshift Galaxies
Lanzetta, Kenneth M.; Yahil, Amos; Fernández-Soto, Alberto
We apply the Lyman absorption signature to search for galaxies at redshifts z ~ 6-17 using optical and infrared images of the Hubble Deep Field. The infrared images are sensitive to a point-source 5 sigma detection threshold of AB(22,000) = 23.8, which, adopting plausible assumptions to relate rest-frame ultraviolet flux densities to unobscured st…
The Orbits of the Inner Uranian Satellites from Hubble Space Telescope and Voyager 2 Observations
Jacobson, R. A.
This article presents revised orbital elements for the 10 small Uranian satellites discovered by the Voyager 2 spacecraft. The elements have been determined from a fit to astrometric observations made with the Hubble Space Telescope and imaging data acquired by Voyager 2. An assessment of the accuracy of the orbits represented by the elements is p…