TY - JOUR
T1 - Galactic nebular lines in the fibre spectra of background QSOs
T2 - Reaching a hundred QSO-galaxy pairs with spectroscopic and photometric measurements
AU - Straka, Lorrie A.
AU - Noterdaeme, Pasquier
AU - Srianand, Raghunathan
AU - Nutalaya, Songkiat
AU - Kulkarni, Varsha P.
AU - Khare, Pushpa
AU - Bowen, David
AU - Bishof, Michael
AU - York, Donald G.
N1 - Publisher Copyright:
© 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2015/3/11
Y1 - 2015/3/11
N2 - We present photometric and spectroscopic measurements of 53 QSO-galaxy pairs from the Sloan Digital Sky Survey (SDSS),where nebular emission lines from a 0 < z < 0.84 foreground galaxy are detected in the fibre spectra of a background QSO, bringing the overall sample to 103 QSO-galaxy pairs detected in the SDSS. We here study the nature of these systems. Detected foreground galaxies appear at impact parameters between 0.37 and 12.68 kpc. The presence of oxygen and Balmer emission lines allows us to determine the emission linemetallicities for our sample, which are on average supersolar in value. Star formation rates for our sample are in the range 0.01-12 M⊙ yr-1. We utilize photometric redshift fitting techniques to estimate the M* values of our galaxies (log M* =7.34-11.54), and extrapolate this relationship to those galaxies with no imaging detections.Where available, we measure the absorption features present in the QSO spectrum due to the foreground galaxy and the relationships between their rest equivalent widths. We report an anticorrelation between impact parameter and E(B - V)(g - i), as well as a correlation between galaxy colour (u - r) and E(B - V)(g - i). We find that our sample is one of late-type, star-forming galaxies comparable to field galaxies in a similar redshift range, providing important clues to better understand absorption systems. These galaxies represent a sample of typical galaxies in the local Universe for which abundances, extinction, morphology, and absorption properties may be measured using background QSOs with great potential for follow-up observations.
AB - We present photometric and spectroscopic measurements of 53 QSO-galaxy pairs from the Sloan Digital Sky Survey (SDSS),where nebular emission lines from a 0 < z < 0.84 foreground galaxy are detected in the fibre spectra of a background QSO, bringing the overall sample to 103 QSO-galaxy pairs detected in the SDSS. We here study the nature of these systems. Detected foreground galaxies appear at impact parameters between 0.37 and 12.68 kpc. The presence of oxygen and Balmer emission lines allows us to determine the emission linemetallicities for our sample, which are on average supersolar in value. Star formation rates for our sample are in the range 0.01-12 M⊙ yr-1. We utilize photometric redshift fitting techniques to estimate the M* values of our galaxies (log M* =7.34-11.54), and extrapolate this relationship to those galaxies with no imaging detections.Where available, we measure the absorption features present in the QSO spectrum due to the foreground galaxy and the relationships between their rest equivalent widths. We report an anticorrelation between impact parameter and E(B - V)(g - i), as well as a correlation between galaxy colour (u - r) and E(B - V)(g - i). We find that our sample is one of late-type, star-forming galaxies comparable to field galaxies in a similar redshift range, providing important clues to better understand absorption systems. These galaxies represent a sample of typical galaxies in the local Universe for which abundances, extinction, morphology, and absorption properties may be measured using background QSOs with great potential for follow-up observations.
KW - Cosmology: observations
KW - Galaxies: evolution
KW - Galaxies: photometry
KW - Quasars: absorption lines
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U2 - 10.1093/mnras/stu2739
DO - 10.1093/mnras/stu2739
M3 - Article
AN - SCOPUS:85014774359
SN - 0035-8711
VL - 447
SP - 3856
EP - 3872
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -