Search Publications
Ultraviolet Emission from the Liner Nucleus of NGC 6500
Filippenko, Alexei V.; Ho, Luis C.; Shields, Joseph C. +3 more
As a step towards clarifying the ionization mechanism of LINERs, we have used the Hubble Space Telescope Faint Object Spectrograph to obtain an ultraviolet spectrum of the nucleus of NGC 6500. This is the first time that such a spectrum has been taken of a "LINER 2" nucleus-that is, a LINER lacking broad permitted emission lines like those in Type…
Mass Segregation and Equipartition of Energy in Two Globular Clusters with Central Density Cusps.
Sosin, Craig
We begin by presenting the analysis of a set of deep B- and V-band images of the central density cusp of the globular cluster M30 (NGC 7099), taken with the Faint Object Camera aboard the Hubble Space Telescope. These images are the first to resolve lower-mass main-sequence stars in the cluster's central 10". From the positions of individual stars…
UIT: Ultraviolet Observations of the Small Magellanic Cloud
Parker, Joel Wm.; O'Connell, R. W.; Bohlin, R. C. +9 more
A mosaic of four UIT far-UV (FUV) (lambda_ {eff} = 1620 Angstroms) images, with derived stellar and HII region photometry, is presented for most of the Bar of the SMC. The UV morphology of the SMC's Bar shows that recent star formation there has left striking features including: a) four concentrations of UV-bright stars spread from northeast to so…
HST Images of the High-Excitation Herbig-Haro Object HH 32
Noriega-Crespo, A.; Raymond, J.; Curiel, S. +2 more
We present high angular resolution emission-line and continuum images of the remarkable Herbig-Haro jet HH 32 obtained with the Wide Field and Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope. We have obtained narrow band [S ii] λλ6716,673l, [N ii] 6583 and Hα images, as well as an R continuum image, of this HH jet. The 0."l spatial re…
Ultraviolet Imaging of the Globular Cluster 47 Tucanae
O'Connell, Robert W.; Bohlin, Ralph C.; Landsman, Wayne B. +8 more
We have used the Ultraviolet Imaging Telescope to obtain far-UV (1620 Å), wide field (40' diameter) images of the prototypical metal-rich globular cluster 47 Tucanae. We find a population of about 20 hot (Teff>9000 K) objects near or above the predicted UV luminosity of the hot horizontal branch (HB) and lying within two half-light r…
HST synthetic spectral analysis of U GEM in early and late quiescence: A heated white dwarf and accretion belt?
Horne, Keith; Sion, E. M.; Huang, M. +3 more
We have re-examined two archival HST FOS G130H spectra of the prototype dwarf nova U Geminorum obtained during its quiescence 13 days and 70 days after a wide outburst. Using synthetic spectral fitting with two flux-emitting components, a slowly rotating white dwarf photosphere, and a rapidly spinning accretion belt (Vrot sin i=3200 km …
Near Infrared Imaging of the Hubble Deep Field with the Keck Telescope
Hogg, David W.; Matthews, K.; Soifer, B. T. +4 more
Two deep K-band (2.2 microns ) images, with point-source detection limits of K=25.2 mag (one sigma), taken with the Keck Telescope in subfields of the Hubble Deep Field, are presented and analyzed. A sample of objects to K=24 mag is constructed and V606-I814 and I814-K colors are measured. By stacking visually sele…
The Nuclear Region of M51 Imaged with the HST Planetary Camera
Lauer, Tod R.; Faber, S. M.; Grillmair, Carl J. +4 more
We present high-resolution, broad- and narrow-band, pre-refurbishment images of the central region of M51 taken with the Planetary Camera of the Hubble Space Telescope. The V-band images show a rather chaotic distribution of dust lanes, though some are oriented radially, roughly aligned with the major axis of the bar, and may be transporting gas t…
Globular Cluster Photometry with the Hubble Space Telescope.VI.WF/PC-I Observations of the Stellar Populations in the Core of M13 (NGC 6205)
Schneider, Donald P.; Yanny, Brian; Bahcall, John N. +2 more
We study the dense core of the globular cluster Messier 13 (NGC 6205) using pre-refurbishment Planetary Camera-I images obtained with the Hubble Space Telescope. Short exposures (60 s) through the F555W and F785LP filters (similar to Johnson V and I, respectively) have been used to obtain V and I photometry of 2877 stars brighter than V ~ 20 in a …
The Axis Ratio Distribution of Local and Distant Galaxies
Windhorst, Rogier A.; Burstein, David; Odewahn, Stephen C.
Surface photometry from 16 HST/WFPC2 fields in the I814-band filter is used to derive the distribution of apparent axis ratios for galaxies in progressively fainter magnitude intervals for I814≤25. We assess the systematic and accidental errors in ellipticity measurements as a function of image resolution and signal-to-noise …