Search Publications
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…
Deep HST/FOC Imaging of the Central Density Cusp of the Globular Cluster M15
King, Ivan R.; Sosin, Craig
Using the Faint Object Camera on the repaired Hubble Space Telescope, we have observed two fields in the globular cluster M15:\ the central density cusp, and a field at r = 20''. These are the highest-resolution images ever taken of this cluster's dense core, and are the first to probe the distribution of stars well below the main-sequence turnoff…
Absolute Flux Distributions of Solar Analogs from the UV to the Near-IR
Colina, Luis; Bohlin, Ralph
The 0.225-2.695mu m absolute flux distributions of the solar analogs P041C, P177D, and P330E are presented. The ultraviolet and optical wavelength range from 0.225mu m to 0.825mu m is based on high signal-to-noise spectra obtained with the HST Faint Object Spectrograph (FOS). The spectra in the near-infrared longward of 0.825mu m are scaled versio…
Interstellar Gas in Low Mass Virgo Cluster Spiral Galaxies
Madden, Suzanne C.; Smith, Beverly J.
We have measured the strengths of the [C II] 158 mu m, [N II] 122 mu m, and CO (1 - 0) lines from five low blue luminosity spiral galaxies in the Virgo Cluster, using the Infrared Space Observatory and the NRAO 12m millimeter telescope. Two of the five galaxies have high L([C II])/L(CO) and L(FIR)/L(CO) ratios compared to higher mass spirals. Thes…
High-Resolution Imagery of BD + 30degree3639 and Its Dusty Halo
White, Stephen M.; Borkowski, Kazimierz J.; Harrington, J. Patrick +1 more
The planetary nebula BD +30\arcdeg3639 has been imaged by the Hubble Space Telescope through nine narrow-band filters. A high resolution radio map has been obtained with the VLA. Comparison of Hβ , Hα and radio images allow us to derive the point-to-point variations in both the extinction and the ratio of total to selective absorption. The extinct…
Observations of Structures in the Inner Coma of Chiron with the HST Planetary Camera
Samarasinha, Nalin H.; Buie, Marc W.; Mueller, Beatrice E. A. +2 more
We have obtained a series of images of 2060 Chiron with the HST Planetary Camera on 3 nights near its minimum geocentric distance in 1993 (Delta = 8.342 AU). Extended structure was visible within a radial distance of 0.3'' from the nucleus. We interpret the structure to be the bound ballistic atmosphere and exopause boundary (at R_e~ 1800 km) hypo…
Distance to the Coma Cluster and a Value for HO Inferred from Globular Clusters in IC 4051
Ajhar, Edward A.; Grillmair, Carl J.; Groth, Edward J. +4 more
We report HST-WFPC2 observations of the giant E2 galaxy IC 4051 located 14' east of the center of the Coma Cluster. Eight full-orbit exposures were obtained with the F606W filter, and two with the F814W filter. Counts of globular clusters (GCs) in 0.2-mag wide bins were made within the PC1 (f/28) frame, where faint GCs can be distinguished from no…
A New Pulsation Spectrum and Asteroseismology of delta Scuti.
Templeton, Matthew R.; Bradley, Paul A.; Guzik, Joyce A. +3 more
We present the results of a five-year Strömgren y photometric campaign on δ Scuti. Our data set consists of 6515 discrete differential magnitudes, and spans the period of 1983 June to 1988 September. We found the primary pulsation mode at 59.731129±0.000002 µHz, in close agreement with the frequency determination of Fitch (1976, IAU Colloqui…