The BOSS Lyman-alpha Forest Sample from SDSS Data Release 9
Abstract
We present the BOSS Lyman-alpha (Lya) Forest Sample from SDSS Data Release 9, comprising 54,468 quasar spectra with zqso > 2.15 suitable for Lya forest analysis. This data set probes the intergalactic medium with absorption redshifts 2.0 < z_alpha < 5.7 over an area of 3275 square degrees, and encompasses an approximate comoving volume of 20 h^-3 Gpc^3. With each spectrum, we have included several products designed to aid in Lya forest analysis: improved sky masks that flag pixels where data may be unreliable, corrections for known biases in the pipeline estimated noise, masks for the cores of damped Lya systems and corrections for their wings, and estimates of the unabsorbed continua so that the observed flux can be converted to a fractional transmission. The continua are derived using a principal component fit to the quasar spectrum redwards of restframe Lya (lambda > 1216 Ang), extrapolated into the forest region and normalized by a linear function to fit the expected evolution of the Lya forest mean-flux. The estimated continuum errors are ~5% rms. We also discuss possible systematics arising from uncertain spectrophotometry and artifacts in the flux calibration; global corrections for the latter are provided. Our sample provides a convenient starting point for users to analyze clustering in BOSS Lya forest data, and it provides a fiducial data set that can be used to compare results from different analyses of baryon acoustic oscillations in the Lya forest. The full data set is available from the SDSS-III DR9 web site.
Cite
@article{arxiv.1211.5146,
title = {The BOSS Lyman-alpha Forest Sample from SDSS Data Release 9},
author = {Khee-Gan Lee and Stephen Bailey and Leslie E. Bartsch and William Carithers and Kyle S. Dawson and David Kirkby and Britt Lundgren and Daniel Margala and Nathalie Palanque-Delabrouille and Matthew M. Pieri and David J. Schlegel and David H. Weinberg and Christophe Yeche and Eric Aubourg and Julian Bautista and Dmitry Bizyaev and Michael Blomqvist and Adam S. Bolton and Arnaud Borde and Howard Brewington and Nicolas G. Busca and Rupert A. C. Croft and Timothee Delubac and Garrett Ebelke and Daniel J. Eisenstein and Andreu Font-Ribera and Jian Ge and Jean-Christophe Hamilton and Joseph F. Hennawi and Shirley Ho and Klaus Honscheid and Jean-Marc Le Goff and Elena Malanushenko and Viktor Malanushenko and Jordi Miralda-Escude and Adam D. Myers and Pasquier Noterdaeme and Daniel Oravetz and Kaike Pan and Isabelle Paris and Patrick Petitjean and James Rich and Emmanuel Rollinde and Nicholas P. Ross and Graziano Rossi and Donald P. Schneider and Audrey Simmons and Stephanie Snedden and Anze Slosar and David N. Spergel and Nao Suzuki and Matteo Viel and Benjamin A. Weaver},
journal= {arXiv preprint arXiv:1211.5146},
year = {2014}
}
Comments
15 pages, 11 figures; Submitted to AJ