THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY: QUASAR TARGET SELECTION FOR DATA RELEASE NINE

By N. Ross, A. Myers, Erin Sheldon, C. Yéche, M. Strauss, Jo Bovy, J. Kirkpatrick, Gordon Richards, E. Aubourg, M. Blanton and 29 more. 2011

271 citations recorded by the source corpus.

The SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), a five-year spectroscopic survey of 10,000 deg2, achieved first light in late 2009. One of the key goals of BOSS is to measure the signature of baryon acoustic oscillations (BAOs) in the distribution of Lyα absorption from the spectra of a sample of ∼150,000 z > 2.2 quasars. Along with measuring the angular diameter distance at z ≈ 2.5, BOSS will provide the first direct measurement of the expansion rate of the universe at z > 2. One of the biggest challenges in achieving this goal is an efficient target selection algorithm for quasars in the redshift range 2.2 < z < 3.5, where their colors tend to overlap those of the far more numerous stars. During the first year of the BOSS survey, quasar target selection (QTS) methods were developed and tested to meet the requirement of delivering at least 15 quasars deg−2 in this redshift range, with a goal of 20 out of 40 targets deg−2 allocated to the quasar survey. To achieve these surface densities, the magnitude limit of the quasar targets was set at g ⩽ 22.0 or r ⩽ 21.85. While detection of the BAO signature in the distribution of Lyα absorption in quasar spectra does not require a uniform target selection algorithm, many other astrophysical studies do. We have therefore defined a uniformly selected subsample of 20 targets deg−2, for which the selection efficiency is just over 50% (∼10 z > 2.20 quasars deg−2). This “CORE” subsample will be fixed for Years Two through Five of the survey. For the remaining 20 targets deg−2, we will continue to develop improved selection techniques, including the use of additional data sets beyond the Sloan Digital Sky Survey (SDSS) imaging data. In this paper, we describe the evolution and implementation of the BOSS QTS algorithms during the first two years of BOSS operations (through 2011 July), in support of the science investigations based on these data, and we analyze the spectra obtained during the first year. During this year, 11,263 new z > 2.20 quasars were spectroscopically confirmed by BOSS, roughly double the number of previously known quasars with z > 2.20. Our current algorithms select an average of 15 z > 2.20 quasars deg−2 from 40 targets deg−2 using single-epoch SDSS imaging. Multi-epoch optical data and data at other wavelengths can further improve the efficiency and completeness of BOSS QTS.

Subfields: Astronomy and Astrophysics, Instrumentation

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Instrumentation

Citations in the corpus

Validation of the Scientific Program for the Dark Energy Spectroscopic Instrument (2023, background): “The selection of quasar samples has historically relied on identification through excess UV emission (Richards et al. 2002; Ross et al. 2012).”
The Sloan Digital Sky Survey Quasar Catalog: Fourteenth data release (2017, background): “The two peaks at z ∼ 0.8 and z ∼ 1.6 are due to known degeneracies in the associated quasar target selection (see Ross et al. 2012, for more details).”
Baryon acoustic oscillations in the Lyα forest of BOSS DR11 quasars (2014, methodology): “The quasar spectroscopy targets are selected from photometric data via a combination of algorithms (Richards et al., 2009; Yeche et al., 2009; Kirkpatrick et al., 2011; Bovy et al., 2011; Palanque-Delabrouille et al., 2011), as summarized in Ross et al. (2012).”
The Completed SDSS-IV Extended Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations with Lyα Forests (2020, methodology): “The quasar target selection algorithms for BOSS are summarized in Ross et al. (2012), and those for eBOSS are summarized in Myers et al. (2015).”
Evolution of the AGN UV luminosity function from redshift 7.5 (2018, background): “The lower cut z > 3.7 in SDSS limits the impact of systematic uncertainties in the Richards et al. (2006) selection function (Prochaska et al. 2009; Worseck & Prochaska 2011).”
THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: TECHNICAL OVERVIEW (2014, background): “Most of these quasars were targeted by the SDSS-III BOSS survey for spectroscopy (see Ross et al. 2012; C. P. Ahn et al. 2015, in preparation for details regarding the final quasar target selection in BOSS).”
The Sloan Digital Sky Survey Reverberation Mapping Project: Sample Characterization (2018, background): “As detailed in Ross et al. (2012), the BOSS quasar survey combines optical color selection with a variety of ancillary target selection criteria to increase the total number of quasars.”
THE SDSS-IV EXTENDED BARYON OSCILLATION SPECTROSCOPIC SURVEY: QUASAR TARGET SELECTION (2015, methodology): “Objects classified as having excellent prior spectroscopy are those that are of SDSS provenance and match the sample used to define known objects in BOSS (see Ross et al. 2012), or those that match the final BOSS quasar catalog (DR12Q ; c.f. Pâris et al. 2014).”
Baryon acoustic oscillations from the cross-correlation of Lyα absorption and quasars in eBOSS DR14 (2019, methodology): “The quasar target selection for BOSS, summarized in Ross et al. (2012), combines different targeting methods described in Yèche et al. (2010), Kirkpatrick et al. (2011), and Bovy et al. (2011).”
THE NINTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY: FIRST SPECTROSCOPIC DATA FROM THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY (2012, methodology): “However, to allow statistical studies of quasar physical properties, demographics, and clustering, we defined a subsample (called “CORE” in Ross et al. 2012) that will be uniformly selected throughout BOSS.”
THE SDSS-IV EXTENDED BARYON OSCILLATION SPECTROSCOPIC SURVEY: OVERVIEW AND EARLY DATA (2015, background): “These systematics have already been extensively studied within BOSS (Ross et al. 2011, 2012a; Ho et al. 2012; Pullen & Hirata 2013), and the greater volume and greater statistical power at large scales from eBOSS will place new demands on homogeneity of the target samples.”
THE BARYON OSCILLATION SPECTROSCOPIC SURVEY OF SDSS-III (2012, methodology): “The selection of galaxy and quasar targets are described in Padmanabhan et al. (2012b) and Ross et al. (2012b), respectively, the spectrograph design and performance in Smee et al. (2012), and the spectral data reductions in Schlegel et al. (2012) and Bolton et al. (2012b).”