Search Publications

The spectrum of the young star HD 100546 observed with the Infrared Space Observatory
Bibcode: 1998A&A...332L..25M

Waters, L. B. F. M.; Vandenbussche, B.; Waelkens, C. +3 more

It is generally assumed that planets form in the dusty disks that surround young stars (Beckwith & Sargent 1996). The Infrared Space Observatory (Kessler et al. 1996) now enables us to determine the characteristics of these disks with unprecedented spectral resolution and signal-to-noise. We present here ISO spectra of the disk that surrounds …

1998 Astronomy and Astrophysics
ISO 320
High-z Lyalpha Emitters. I. A Blank-Field Search for Objects near Redshift Z = 3.4 in and around the Hubble Deep Field and the Hawaii Deep Field SSA 22
DOI: 10.1086/300309 Bibcode: 1998AJ....115.1319C

Cowie, Lennox L.; Hu, Esther M.

We present deep narrowband (lambda = 5390 Å, Deltalambda = 77 Å) and multicolor observations of the Hubble Deep Field and the Hawaii Deep Field SSA 22 obtained with the LRIS instrument at the 10 m Keck II Telescope. It is shown that there is a substantial population of galaxies at z ~ 3.4 that can be selected by Lyalpha emission. Comparison with c…

1998 The Astronomical Journal
eHST 316
The Nature and Evolution of Ultraluminous Infrared Galaxies:A Mid-Infrared Spectroscopic Survey
DOI: 10.1086/311614 Bibcode: 1998ApJ...505L.103L

Lutz, D.; Genzel, R.; Rigopoulou, D. +2 more

We report the first results of a low-resolution mid-infrared spectroscopic survey of an unbiased, far-infrared-selected sample of 60 ultraluminous infrared galaxies (ULIRGs) (LIR>1012 Lsolar) using ISOPHOT-S on board the Infrared Space Observatory (ISO). We use the ratio of the 7.7 µm ``polycyclic aromatic…

1998 The Astrophysical Journal
ISO 305
The Hubble Space Telescope Key Project on the Extragalactic Distance Scale. XIII. The Metallicity Dependence of the Cepheid Distance Scale
DOI: 10.1086/305538 Bibcode: 1998ApJ...498..181K

Illingworth, Garth D.; Huchra, John P.; Madore, Barry F. +22 more

Uncertainty in the metal-abundance dependence of the Cepheid variable period-luminosity (PL) relation remains one of the outstanding sources of systematic error in the extragalactic distance scale and in the Hubble constant. To test for such a metallicity dependence, we have used the Wide Field Planetary Camera 2 (WFPC2) on the Hubble Space Telesc…

1998 The Astrophysical Journal
eHST 297
Weak Lensing Analysis of CL 1358+62 Using Hubble Space Telescope Observations
DOI: 10.1086/306102 Bibcode: 1998ApJ...504..636H

Franx, Marijn; Hoekstra, Henk; Kuijken, Konrad +1 more

We report on the detection of weak gravitational lensing of faint, distant background objects by Cl 1358+62, a rich cluster of galaxies at a redshift of z = 0.33. The observations consist of a large, multicolor mosaic of Hubble Space Telescope WFPC2 images. The number density of approximately 50 background objects arcmin-2 allows us to …

1998 The Astrophysical Journal
eHST 289
Morphological Studies of the Galaxy Populations in Distant ``Butcher-Oemler'' Clusters with the Hubble Space Telescope. II. AC 103, AC 118, and AC 114 at Z = 0.31
DOI: 10.1086/305462 Bibcode: 1998ApJ...497..188C

Smail, Ian; Ellis, Richard S.; Barger, Amy J. +2 more

We present new results of a program to study the detailed morphologies of galaxies in intermediate-redshift clusters and hence understand the physical origin of the enhanced star formation seen in these environments at earlier epochs. Deep, high-resolution imagery has been obtained of three rich clusters, AC 103, AC 118, and AC 114 at z = 0.31, th…

1998 The Astrophysical Journal
eHST 288
Hubble Space Telescope Imaging of the CFRS and LDSS Redshift Surveys. II. Structural Parameters and the Evolution of disk Galaxies to z ~ 11
DOI: 10.1086/305713 Bibcode: 1998ApJ...500...75L

Tresse, Laurence; Brinchmann, Jarle; Ellis, Richard +10 more

Several aspects of the evolution of star-forming galaxies are studied using measures of the two-dimensional surface brightness profiles extracted from Hubble Space Telescope images of a sample of 341 faint objects selected from the CFRS and LDSS redshift surveys. The galaxies have 0 < z < 1.3. The size function of disk scale lengths in disk-…

1998 The Astrophysical Journal
eHST 279
The Solar Corona Above Polar Coronal Holes as Seen by SUMER on SOHO
DOI: 10.1086/305756 Bibcode: 1998ApJ...500.1023W

Wilhelm, Klaus; Marsch, Eckart; Dwivedi, Bhola N. +4 more

In order to address two of the principal scientific objectives of the Solar and Heliospheric Observatory (SOHO), studies of the heating mechanisms of the solar corona and the acceleration processes of the solar wind, we deduce electron temperatures, densities, and ion velocities in plumes and interplume regions of polar coronal holes using ultravi…

1998 The Astrophysical Journal
SOHO 274
HST study of Lyman-alpha emission in star-forming galaxies: the effect of neutral gas flows
DOI: 10.48550/arXiv.astro-ph/9802253 Bibcode: 1998A&A...334...11K

Mas-Hesse, J. M.; Terlevich, E.; Terlevich, R. +3 more

We present high dispersion HST GHRS UV spectroscopic observations of 8 H II galaxies covering a wide range of metallicities and physical properties. We have found Lyalpha \ emission in 4 galaxies with blueshifted absorption features, leading to P Cygni like profiles in 3 of them. In all these objects the O I and Si II absorption lines are also blu…

1998 Astronomy and Astrophysics
IUE eHST 274
The Ultraviolet Spectroscopic Properties of Local Starbursts: Implications at High Redshift
DOI: 10.1086/306035 Bibcode: 1998ApJ...503..646H

Robert, Carmelle; Heckman, Timothy M.; Leitherer, Claus +2 more

We report the results of a systematic study of the vacuum ultraviolet (λ ~= 1150-2000 Å) spectra of a sample of 45 starburst and related galaxies observed with the IUE satellite. These span broad ranges in metallicity (from 0.02 to 3 times solar), bolometric luminosity (~107-4 × 1011 L), and galaxy properties (e.g…

1998 The Astrophysical Journal
IUE 262