2 citations · 4 across the 3 of their papers we have counts for
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Inhomogeneous Absorbers and Derived Column Densities
Bassem M. Sabra, Fred Hamann
We study the dependence of column densities derived from absorption lines on the spatial distribution of the ions in an absorber. In particular, we investigate four varieties of co…
Quasar Elemental Abundances and Host Galaxy Evolution
F. Hamann, M. Dietrich, B. Sabra +1
High redshift quasars mark the locations where massive galaxies are rapidly being assembled and forming stars. There is growing evidence that quasar environments are metal-rich out…
How Massive Are BALQSO Winds?
F. Hamann, B. Sabra, V. Junkkarinen +2
We are involved in a program to derive properties of broad absorption line (BAL) winds in quasars using combined UV and X-ray observations. A major obstacle is large uncertainties…
PG 1254+047: An Intrinsically X-ray Weak, Heavily Absorbed BALQSO?
Bassem M. Sabra, Fred Hamann
We present \textit{Chandra} observations of the radio-quiet Broad Absorption Line (BAL) QSO PG 1254+047. We find that it is a weak X-ray source, with a total of photons m…
X-Ray Absorption Associated with High-Velocity UV Absorbers
B. M. Sabra, F. Hamann, J. C. Shields +2
We present Chandra observations of two radio-quiet QSOs, PG 2302+029 and PG 1254+047. PG 2302+029 has an ultra high-velocity UV absorption system -56,000 km/s, while PG 1254+047 is…