Abstract:

We measure the large-scale cross-correlation of quasars with the Lymanalpha forest absorption, using over 164,000 quasars from Data Release 11of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend theprevious study of roughly 60,000 quasars from Data Release 9 to largerseparations, allowing a measurement of the Baryonic Acoustic Oscillation(BAO) scale along the line of sight $c/(H(z=2.36) ~ r_s) = 9.0 \pm 0.3$and across the line of sight $D_A(z=2.36)~ / ~ r_s = 10.8 \pm 0.4$,consistent with CMB and other BAO data. Using the best fit value of thesound horizon from Planck data ($r_s=147.49 Mpc$), we can translatethese results to a measurement of the Hubble parameter of $H(z=2.36) =226 \pm 8 km/s$ and of the angular diameter distance of $D_A(z=2.36) =1590 \pm 60 Mpc$. The measured cross-correlation function and an updateof the code to fit the BAO scale (baofit) are made publicly available.

Notes:

26 pages, 7 figures, submitted to JCAP

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