We present the Data Release 9 Quasar (DR9Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the survey, are spectrocopically confirmed as quasars via visual inspection, have luminosities M i [z = 2] < −20.5 (in a ΛCDM cosmology with H 0 = 70 km s −1 Mpc −1 , Ω M = 0.3, and Ω Λ = 0.7) and either display at least one emission line with full width at half maximum (FWHM) larger than 500 km s −1 or, if not, have interesting/complex absorption features. It includes as well, known quasars (mostly from SDSS-I and II) that were reobserved by BOSS. This catalog contains 87 822 quasars (78 086 are new discoveries) detected over 3275 deg 2 with robust identification and redshift measured by a combination of principal component eigenspectra newly derived from a training set of 8632 spectra from SDSS-DR7. The number of quasars with z > 2.15 (61 931) is ∼2.8 times larger than the number of z > 2.15 quasars previously known. Redshifts and FWHMs are provided for the strongest emission lines (C iv, C iii], Mg ii). The catalog identifies 7533 broad absorption line quasars and gives their characteristics. For each object the catalog presents five-band (u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3600−10 500 Å at a spectral resolution in the range 1300 < R < 2500; the spectra can be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 949 quasars that have been identified, among galaxy targets of the BOSS or among quasar targets after DR9 was frozen.

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We present the serendipitous discovery of an extremely broad (ΔV LSR ∼ 150 km s−1), faint (T mb < 10 mK), and ubiquitous 1667 and 1665 MHz ground-state thermal OH emission toward the second quadrant of the outer Galaxy (R gal > 8 kpc) with the Green Bank Telescope. Originally discovered in 2015, we describe the redundant experimental, observational, and data quality tests of this result over the last five years. The longitude–velocity distribution of the emission unambiguously suggests large-scale Galactic structure. We observe a smooth distribution of OH in radial velocity that is morphologically similar to the H i radial velocity distribution in the outer Galaxy, showing that molecular gas is significantly more extended in the outer Galaxy than previously expected. Our results imply the existence of a thick (−200 pc < z < 200 pc) disk of diffuse ( n H 2 ∼ 5 × 10−3 cm−3) molecular gas in the outer Galaxy previously undetected in all-sky 12CO surveys.

We present excitation temperatures T ex for the OH 18-cm main lines at 1665 and 1667 MHz measured directly in front of the W5 star-forming region, using observations from the Green Bank Telescope and the Very Large Array. We find unequivocally that T ex at 1665 MHz is greater than T ex at 1667 MHz. Our method exploits variations in the continuum emission from W5, and the fact that the continuum brightness temperatures T C in this nebula are close to the excitation temperatures of the OH lines in the foreground gas. The result is that an OH line can appear in emission in one location and in absorption in a neighboring location, and the value of T C where the profiles switch from emission to absorption indicates T ex . Absolute measurements of T ex for the main lines were subject to greater uncertainty because of unknown effects of geometry of the OH features. We also employed the traditional "expected profile" method for comparison with our "continuum background" method, and found that the continuum background method provided more precise results, and was the one to definitively show the T ex difference. Our best estimate values are: T 65 ex = 6.0 ± 0.5 K, T 67 ex = 5.1 ± 0.2 K, and T 65 ex − T 67 ex = 0.9 ± 0.5 K. The T ex values we have measured for the ISM in front of W5 are similar to those found in the quiescent ISM, indicating that proximity to massive star-forming regions does not generally result in widespread anomalous excitation of OH emission.