Lennox L. Cowie

Metal enrichment and ionization balance in the Lyman alpha forest at z = 3

The recent discovery of carbon in close to half of the low neutral hydrogen column density [

The Chandra Deep Survey of the Hubble Deep Field-North Area. II. Results from the Caltech Faint Field Galaxy Redshift Survey Area*

N({\rm H~I}) > 3\ten{14}\cm2

Optical and Infrared Properties of the 2 Ms Chandra Deep Field North X-Ray Sources

] Lyman forest clouds toward

High-z Lyα 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

z \sim 3

Mapping the Evolution of High-Redshift Dusty Galaxies with Submillimeter Observations of a Radio-selected Sample

quasars has challenged the widely held view of this forest as a chemically pristine population uniformly distributed in the intergalactic medium, but has not eliminated the possibility that a primordial population might be present as well. Using extremely high signal-to-noise observations of a sample of quasars we now show that \ion{C}{4} can be found in 75% of clouds with

THE TEAM KECK TREASURY REDSHIFT SURVEY OF THE GOODS-NORTH FIELD

N({\rm H~I}) > 3\ten{14}\cm2

The Distribution of column densities and b values in the Lyman-alpha forest

and more than 90% of those with

A filter for deep near-infrared imaging

N({\rm H~I}) > 1.6\ten{15}\cm2

The Nature of the Hard X-Ray Background Sources: Optical, Near-Infrared, Submillimeter, and Radio Properties

. Clouds with

The Evolution of Lyman Limit Absorption Systems to Redshift Six

N({\rm H~I}) > 10^{15}\cm2