Bolton, Adam S., Schlegel, David J., Aubourg, Éric, Bailey, Stephen, Bhardwaj, Vaishali, Brownstein, Joel R., Burles, Scott, Chen, Yan-Mei, Dawson, Kyle, Eisenstein, Daniel J., Gunn, James E., Knapp, G. R., Loomis, Craig P., Lupton, Robert H., Maraston, Claudia, Muna, Demitri, Myers, Adam D., Olmstead, Matthew D., Padmanabhan, Nikhil, Pâris, Isabelle, Percival, Will J., Petitjean, Patrick, Rockosi, Constance M., Ross, Nicholas P., Schneider, Donald P. et al. 2012. "Spectral Classification and Redshift Measurement for the SDSS-III Baryon Oscillation Spectroscopic Survey." The Astronomical Journal 144:144. https://doi.org/10.1088/0004-6256/144/5/144
We describe the automated spectral classification, redshift determination, and parameter measurement pipeline in use for the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III (SDSS-III) as of the survey's ninth data release (DR9), encompassing 831,000 moderate-resolution optical spectra. We give a review of the algorithms employed, and describe the changes to the pipeline that have been implemented for BOSS relative to previous SDSS-I/II versions, including new sets of stellar, galaxy, and quasar redshift templates. For the color-selected "CMASS" sample of massive galaxies at redshift 0.4 –1 for both galaxies and quasars, with a significant tail to a few hundreds of km s–1 for quasars. We test the accuracy of these statistical redshift error estimates using repeat observations, finding them underestimated by a factor of 1.19-1.34 for galaxies and by a factor of two for quasars. We assess the impact of sky-subtraction quality, signal-to-noise ratio, and other factors on galaxy redshift success. Finally, we document known issues with the BOSS DR9 spectroscopic data set and describe directions of ongoing development.
