Search Publications
Cluster - Science and Mission Overview
Escoubet, C. P.; Goldstein, M. L.; Schmidt, R.
The Electric Field and Wave Experiment for the Cluster Mission
Thomsen, M.; Wygant, J.; Gustafsson, G. +24 more
Discovery of Extended Blue Horizontal Branches in Two Metal-rich Globular Clusters
Rich, R. Michael; Renzini, Alvio; Piotto, Giampaolo +7 more
We have used WFPC2 to construct B, V color-magnitude diagrams of four metal-rich globular clusters, NGC 104 (47 Tuc), NGC 5927, NGC 6388, and NGC 6441. All four clusters have well populated red horizontal branches (RHB), as expected for their metallicity. However, NGC 6388 and 6441 also exhibit a prominent blue horizontal-branch (BHB) extension, i…
Evolution of the Galaxy Population Based on Photometric Redshifts in the Hubble Deep Field
Yee, H. K. C.; Lin, H.; Sawicki, M. J.
This paper presents the results of a photometric redshift study of galaxies in the Hubble Deep Field (HDF). The method of determining redshifts from broadband colors is described, and the dangers inherent in using it to estimate redshifts, particularly at very high z, are discussed. In particular, the need for accurate high-z spectral energy distr…
The Nature of Compact Galaxies in the Hubble Deep Field. II. Spectroscopic Properties and Implications for the Evolution of the Star Formation Rate Density of the Universe1,
Illingworth, Garth D.; Faber, S. M.; Koo, David C. +5 more
We present a spectroscopic study of 51 compact field galaxies with redshifts z < 1.4 and apparent magnitudes I814 < 23.74 in the flanking fields of the Hubble Deep Field. These galaxies are compact in the sense that they have small apparent half-light radii (r1/2 <= 0.5") and high surface brightnesses (µI8…
Observations of the Hubble Deep Field with the Infrared Space Observatory - V. Spectral energy distributions, starburst models and star formation history
Elbaz, D.; Danese, L.; Franceschini, A. +16 more
We have modelled the spectral energy distributions of the 13 Hubble Deep Field (HDF) galaxies reliably detected by the Infrared Space Observatory (ISO). For two galaxies the emission detected by ISO is consistent with being starlight or the infrared `cirrus' in the galaxies. For the remaining 11 galaxies there is a clear mid-infrared excess, which…
The Cluster Ion Spectrometry (cis) Experiment
Lundin, R.; Balsiger, H.; Klecker, B. +43 more
A Powerful Nuclear Starburst in the Seyfert Galaxy Markarian 477: Implications for the Starburst-Active Galactic Nucleus Connection
Leitherer, C.; Wilson, A. S.; Heckman, T. M. +5 more
There have been many suggestions that starbursts may play an important role in Seyfert galaxies. Recent analyses of the UV, optical, and near-IR ``featureless continuum'' (FC) in type 2 Seyfert nuclei have provided indirect evidence that the FC may be produced by a compact starburst and that this starburst may provide a power source for the pronou…
Evidence of an Erupting Magnetic Flux Rope: LASCO Coronal Mass Ejection of 1997 April 13
St. Cyr, O. C.; Paswaters, S. E.; Simnett, G. M. +7 more
A coronal mass ejection (CME) observed by LASCO exhibits evidence that its magnetic field geometry is that of a flux rope. The dynamical properties throughout the fields of view of C2 and C3 telescopes are examined. The results are compared with theoretical predictions based on a model of solar flux ropes. It is shown that the LASCO observations a…
Younger and Brighter - New Distances to Globular Clusters Based on HIPPARCOS Parallax Measurements of Local Subdwarfs
Reid, I. Neill
We have used new parallax measurements, obtained by the Hipparcos satellite, of fifteen nearby, metal-poor stars to re-define the subdwarf main-sequence. All of these stars have parallaxes determined to an accuracy of at least 12%. Comparing these measurements against previous ground-based data for nine stars reveals a systematic offset of 5%, in …