Search Publications
Photometric Redshifts and Selection of High-Redshift Galaxies in the NTT and Hubble Deep Fields
Fontana, Adriano; Saracco, Paolo; Moorwood, Alan +5 more
We present and compare in this paper new photometric redshift catalogs of the galaxies in three public fields: the NTT Deep Field, the HDF-N, and the HDF-S. In the case of the NTT Deep Field, we present here a new photometric catalog, obtained by combining the existing BVrI and JKs with new deep U observations acquired with NTT-SUSI2, and which in…
The First US Naval Observatory CCD Astrograph Catalog
Zacharias, N.; Urban, S. E.; Wycoff, G. L. +9 more
The USNO CCD Astrograph (UCA) started an astrometric survey in 1998 February at Cerro Tololo, Chile. This first, preliminary catalog (UCAC1) includes data taken up to 1999 November with about 80% of the Southern Hemisphere covered. Observing continues, and full sky coverage is expected by mid-2003 after moving the instrument to a Northern Hemisphe…
Hubble Space Telescope NICMOS Images of Herbig-Haro Energy Sources: [Fe II] Jets, Binarity, and Envelope Cavities
Bally, John; Rodríguez, Luis F.; Reipurth, Bo +2 more
We have observed seven regions surrounding the driving sources of Herbig-Haro flows using the NICMOS infrared camera on board the Hubble Space Telescope. These Herbig-Haro energy sources, which power the HH 34, 47, 83, 111, 199, 300, and 454 flows, have all been previously detected in the centimeter-wavelength radio continuum. The regions were ima…
The Hubble Deep Field South: Formulation of the Observing Campaign
Ferguson, Henry C.; Lucas, Ray A.; Brown, Thomas M. +51 more
Deep, multiband observations of high Galactic latitude fields are an essential tool for studying topics ranging from Galactic structure to extragalactic background radiation. The Hubble Deep Field (HDF-N) observations obtained in 1995 December established a standard for such narrow, deep surveys. The field has been extensively analyzed by a variet…
A Kinematic Model for the Narrow-Line Region in NGC 4151
Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +6 more
We present a simple kinematic model for the narrow-line region (NLR) of the Seyfert 1 galaxy NGC 4151, based on our previous observations of extended [O III] emission with the Space Telescope Imaging Spectrograph. The model is similar to a biconical radial outflow model developed for the Seyfert 2 galaxy NGC 1068, except that the bicone axis is ti…
The Star Clusters in the Starburst Irregular Galaxy NGC 1569
Gallagher, J. S.; O'Connell, Robert W.; Hunter, Deidre A. +1 more
We examine star clusters in the irregular starburst galaxy NGC 1569 from Hubble Space Telescope images taken with filters F336W, F555W, and F814W. In addition to the two super-star clusters that are well known, we identify 45 other clusters that are compact but resolved. Integrated UVI colors of the clusters span a large range, and comparison with…
Creating Spectral Templates from Multicolor Redshift Surveys
Dickinson, Mark; Budavári, Tamás; Csabai, István +2 more
Understanding how the physical properties of galaxies (e.g., their spectral type or age) evolve as a function of redshift relies on having an accurate representation of galaxy spectral energy distributions. While it has been known for some time that galaxy spectra can be reconstructed from a handful of orthogonal basis templates, the underlying ba…
In Situ Dust Measurements From within the Coma of 1P/Halley: First-Order Approximation with a Dust Dynamical Model
Fulle, M.; Levasseur-Regourd, A. C.; McBride, N. +1 more
In situ measurements of the light locally scattered by cometary dust, as well as the local dust spatial density, are only available for one comet, 1P/Halley. These data were returned from the Optical Probe Experiment (OPE) and the Dust Impact Detection System (DID) aboard the European Space Agency spacecraft Giotto. Due to a detailed calibration o…
Hubble Space Telescope Observations of HE 2-10: Outflows and Young Super-Star Clusters
Leitherer, Claus; Johnson, Kelsey E.; Vacca, William D. +1 more
We use Hubble Space Telescope (HST) WFPC2 optical images and GHRS ultraviolet spectroscopy to examine the recent star formation history and properties of the Wolf-Rayet galaxy He 2-10. The high spatial resolution afforded by HST has allowed the identification of a number of starburst knots, or ``super-star clusters'' (SSCs). The spatial morphology…
Hubble Space Telescope Observations of Star Clusters in NGC 1023: Evidence for Three Cluster Populations?
Brodie, Jean P.; Larsen, Søren S.
Using Hubble Space Telescope images we have carried out a study of cluster populations in the nearby S0 galaxy NGC 1023. In two WFPC2 pointings we have identified 221 cluster candidates. The small distance (~9 Mpc) combined with deep F555W and F814W images allows us to reach about 2 mag below the expected turnover of the globular cluster luminosit…