Baryon Acoustic Oscillations in the BOSS Lyman Alpha Forest
The Baryon Oscillation Spectroscopic Survey (BOSS) has opened the possibility to measure the expansion rate and geometry of the Universe at redshift z>2 using baryon acoustic oscillations (BAO) in the Lyman-alpha forest. I will present the latest measurements of the BAO scale using the Lyman-alpha forest auto-correlation and the quasar-Lyman-alpha forest cross-correlation based on more than 130,000 quasar spectra taken from SDSS-III Data Release 11. By combining the BAO results for the auto- and cross-correlation, the Hubble parameter and the angular diameter distance at z=2.34 are measured to 2% and 3% accuracy, respectively. New advances in the modeling of broadband distortions of the auto-correlation due to quasar continuum fitting enable us to also make significantly more accurate measurements of the large-scale linear bias and redshift-space distortion of the Lyman-alpha forest.