The Flux Auto- and Cross-Correlation of the Lyα Forest. I. Spectroscopy of QSO Pairs with Arcminute Separations and Similar Redshifts

• Published in: The Astrophysical journal. Supplement series Vol. 175; no. 1; pp. 29 - 47
• Main Authors: Marble, Andrew R, Eriksen, Kristoffer A, Impey, Chris D, Bai, Lei, Miller, Lance
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.03.2008
• ISSN: 0067-0049; 1538-4365
• DOI: 10.1086/523852

The Ly alpha forest has opened a new redshlft regime for cosmological investigation. At z > 2 it provides a unique probe of cosmic geometry and an independent constraint on dark energy that is not subject to standard candle or ruler assumptions. In Paper I of this series on using the Ly alpha forest observed in pairs of QSOs for a new application of the Alcock-Paczynski test, we present and discuss the results of a campaign to obtain moderate-resolution spectroscopy (FWHM [unk] 2.5 AA) of the Ly alpha forest in pairs of QSOs with small redshift differences ( Delta z < 0.25, z > 2.2) and arcminute separations (0 < 5'). This data set, composed of seven individual QSOs, 35 pairs, and one triplet, is also well suited for future investigations of the coherence of Ly alpha absorbers on similar to 1 Mpc transverse scales and the transverse proximity effect. We note seven revisions for previously published QSO identifications and/or redshifts.