6 papers · 1 filter
A High Deuterium Abundance at z=0.7; Evidence for Cosmic Inhomogeneity?
J. K. Webb, R. F. Carswell, K. M. Lanzetta +3
Recent HST/GHRS observations of the z = 0.7010 absorber toward the QSO 1718+4807 (selected because of apparently ideal characteristics for measuring D/H) yield a D/H significantly…
The Gaseous Extent of Galaxies and the Origin of \lya Absorption Systems at z < 1
H. -W. Chen, K. M. Lanzetta, J. K. Webb +1
We present initial results of a program to obtain and analyze HST WFPC2 images of galaxies in fields of HST spectroscopic target QSOs. The goal of the program is to investigate how…
The Galaxy-Absorber Cross-Correlation Function
Kenneth M. Lanzetta, John K. Webb, Xavier Barcons
We describe an analysis of the galaxy-absorber cross-correlation function as a function of velocity separation, impact parameter separation, and absorber Lyman alpha equivalent wid…
Photometric Redshifts of Galaxies in the Hubble Deep Field
Kenneth M. Lanzetta, Alberto Fernandez-Soto, Amos Yahil
We describe our application of broad-band photometric redshift techniques to faint galaxies in the Hubble Deep Field. To magnitudes AB(8140) < 26, the accuracy of the photometric r…
Lyman-alpha absorbers arising in galaxy clusters
A. Ortiz-Gil, K. M. Lanzetta, J. K. Webb +1
We present here new GHRS observations of Lyman-alpha absorption lines associated with groups or clusters toward the QSOs 1545+2101 and 0850+4400. In the first case we have identifi…
The Compared Number Density of High-Redshift Galaxies and Lyman αClouds
A. Fernandez-Soto, K. M. Lanzetta, A. Yahil +1
We use our catalog of photometric redshifts in the Hubble Deep Field (HDF) to estimate the Luminosity Function (LF) of galaxies up to z=2. Using the obtained LF and a relationship…