171 citations · 757 across the 21 of their papers we have counts for
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A Survey of Metal Lines at High-redshift (II) : SDSS Absorption Line Studies - OVI line density, space density and gas metallicity at z_abs ~ 3.0
S. Frank, S. Mathur, M. Pieri +1
We have analysed a large data set of OVI absorber candidates found in the spectra of 3702 SDSS quasars, focusing on a subsample of 387 AGN sightlines with an average S/N>5.0, allow…
A Survey of Metal Lines at High-redshift (I) : SDSS Absorption Line Studies - The Methodology and First Search Results for OVI
S. Frank, S. Mathur, M. Pieri +1
We report the results of a systematic search for signatures of metal lines in quasar spectra of the Sloan Digital Sky Survey (SDSS) Data Release 3(DR3), focusing on finding interve…
The Sources of the CDF-N : broadband spectral analyses, absorption measurements and the alpha_ox - L_UV relation
S. Frank, Patrick S. Osmer, S. Mathur
We present broadband properties of sources in the Chandra Deep Field-North with spectroscopic redshifts. The high luminosity and redshift bins are dominated by typical quasars. The…
Disparate MgII Absorption Statistics towards Quasars and Gamma-Ray Bursts : A Possible Explanation
Stephan Frank, Misty C. Bentz, Krzysztof Z. Stanek +4
We examine the recent report by Prochter et al. (2006) that gamma-ray burst (GRB) sight lines have a much higher incidence of strong MgII absorption than quasar sight lines. We pro…
Studying the Variation of the Fine Structure Constant Using Emission Line Multiplets
Dirk Grupe, Anil K. Pradhan, Stephan Frank
As an extension of the method by Bahcall et al. (2004) to investigate the time dependence of the fine structure constant, we describe an approach based on new observations of forbi…
The metal absorption systems of the QSO 0103-260 and the galaxy redshift distribution in the FORS Deep Field
Stephan Frank, Immo Appenzeller, Stefan Noll +1
Using the Uves echelle spectrograph at the ESO VLT, we observed the absorption line spectrum of the QSO 0103-260 in the Fors Deep Field. In addition to the expected Ly-alpha forest…