Search Publications
Calibration of the Surface Brightness Fluctuation Method for use with the Hubble Space Telescope.
Lauer, Tod R.; Ajhar, Edward A.; Dressler, Alan +4 more
This paper presents the calibration of the surface brightness fluctuation (SBF) technique for use with the Wide Field and Planetary Camera-2 (WFPC-2) on the Hubble Space Telescope (HST). The calibration has a color term and zeropoint significantly different from the Kron-Cousins I-band SBF technique developed for ground-based observations. It is a…
Hubble Space Telescope Imaging of the Globular Cluster System Around NGC 5846
Forbes, Duncan A.; Brodie, Jean P.; Huchra, John
Bimodal globular cluster metallicity distributions have now been seen in a handful of large ellipticals. Here we report the discovery of a bimodal distribution in the dominant group elliptical NGC 5846, using the Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2). The two peaks are located at V-I=0.96 and 1.17, which roughly corres…
Hot Interstellar Gas in the Irregular Galaxy NGC 4449
Chu, You-Hua; Bomans, Dominik J.; Hopp, Ulrich
NGC 4449 is an irregular galaxy with a moderately high star formation activity. The massive stars in NGC 4449 have given rise to many bright HII regions, superbubbles, supergiant shells, and ``chimney-like'' radial filaments. ROSAT X-ray observations of NGC4449 have revealed four point-like sources and a wide-spread diffuse emission. The spectral …
Herbig Haro Objects in the Orion Nebula.
Hartigan, Patrick; Axon, David J.; O'Dell, C. R. +4 more
We have used the Hubble Space Telescope to image two regions of the Orion Nebula in low and high ionization emission lines. There appear to be two main systems of Herbig Haro objects in the Orion nebula - a `North' System is centered slightly north of the BN and IRc2 sources, and a `South' System centered south of the Trapezium stars. The North Sy…
HST High-Resolution Images and Maps of Pluto
Stern, S. A.; Trafton, L. M.; Buie, M. W.
We have obtained Hubble Space Telescope (HST) images of Pluto at 410 and 278 nm which resolve numerous distinct albedo provinces on this planet. Our images were obtained using the Faint Object Camera (FOC) of the Hubble Space Telescope between 1994 June 20 and July 01. This dataset is the first longitudinally-complete, rotationally-resolved direct…
Damped Lyalpha Absorption Associated with an Early-Type Galaxy at Redshift z=0.16377.
Meyer, David M.; Chen, Hsiao-Wen; Savaglio, Sandra +8 more
We report new HST and ground-based observations of a damped Lyα absorption system toward the QSO 0850+4400. The redshift of the absorption system is ζ=0.l63770±0.000054 and the neutral hydrogen column density of the absorption system is log N=19.81±0.04 cm-2. The absorption system is by far the lowest redshift confirmed damped Lyα absor…
Deep HST V- and I-Band Observations of Two Globular Clusters in the Halo of M31.
Richer, Harvey B.; Fahlman, Gregory G.; Holland, Stephen
We present deep (V∼=27) V- and I-band stellar photometry of G302 and G312, two globular star clusters in the halo of M31. These data were obtained using the Hubble Space Telescope's Wide Field/Planetary Camera 2. We find iron abundances of [Fe/H]= -1.85±0.12 for G302 and [Fe/H]=-0.56±0.03 for G312, consistent with spectroscopic measurements. The c…
High Velocity Features in the Orion Nebula
Hartigan, Patrick; O'Dell, C. R.; Bally, John +1 more
We have surveyed the inner 7' of the Orion Nebula for high velocity outflows with Fabry-Perot images in [S II] and [O III]. The new survey recovers all known HH objects in the region, and also reveals a number of new high velocity flows. New flows include (1) jets over an arcminute in length that extend from the center of the nebula to HH 202 in t…
The Dwarf Irregular Galaxy Sextans A. I. HST Photometry of the Resolved Stars
Skillman, Evan D.; Saha, A.; Gallagher, J. +6 more
We have used the Hubble Space Telescope to observe the resolved stars of the nearby (D = 1.4 Mpc) dwarf irregular galaxy Sextans A (DDO 75, A 1008-04). The data consist of dithered WFPC2 images in 3 bands: F439W (1 hour), F555W (30 minutes), and F814W (30 minutes). The stellar photometry was extracted using the DoPHOT program developed by Schechte…
Deep WFPC2 and Ground-Based Imaging of a Complete Sample of 3C Quasars and Galaxies.
Stockton, Alan; Ridgway, Susan E.
\tighten We present the results of an HST and ground-based imaging study of a complete 3C sample of z ~ 1 sources, comprising 5 quasars and 5 radio galaxies. We have observed all of the sample in essentially line-free bands at rest-frame 0.33 mu m with WFPC2 and in rest-frame 1 \micron\ images from the ground; we have also observed most of the sam…