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

Abstract

The Lyman-alpha forest has opened a new redshift 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 Lyman-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 ~ 2.5 Angstroms) of the Lyman-alpha forest in pairs of QSOs with small redshift differences (Delta z < 0.25, z > 2.2) and arcminute separations (< 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 Lyman-alpha absorbers on ~ 1 Mpc transverse scales and the transverse proximity effect. We note seven revisions for previously published QSO identifications and/or redshifts.

arXiv comment20 pages

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Cited by in corpus (5)

• The Physics of the Intergalactic Medium
• Pressure Support vs. Thermal Broadening in the Lyman-alpha Forest II: Effects of the Equation of State on Transverse Structure
• Helium reionization and the thermal proximity effect
• The Flux Auto- and Cross-Correlation of the Lyman-alpha Forest. II. Modelling Anisotropies with Cosmological Hydrodynamic Simulations
• X-shooter observations of QSO pairs