The Optical - Infrared Colors of CORALS QSOs: Searching for Dust Reddening Associated With High Redshift Damped Lyman Alpha Systems

Abstract

The presence of dust in quasar absorbers, such as damped Lyman alpha (DLA) systems, may cause the background QSO to appear reddened. We investigate the extent of this potential reddening by comparing the optical-to-infrared (IR) colors of QSOs with and without intervening absorbers. Our QSO sample is based on the Complete Optical and Radio Absorption Line System (CORALS) survey of Ellison et al (2001). We have obtained near-simultaneous B and K band magnitudes for subset of the CORALS sample and supplemented our observations with further measurements published in the literature. To account for redshift-related color changes, the B-K colors are normalized using the Sloan Digital Sky Survey (SDSS) QSO composite. The mean normalized B-K color of the DLA sub-sample is +0.12, whereas the mean for the no-DLA sample is -0.10; both distributions have RMS scatters ~0.5. Neither a student's T-test nor a KS test indicate that there is any significant difference between the two color distributions. Based on simulations which redden the colors of QSOs with intervening DLAs, we determine a reddening limit which corresponds to E(B-V) < 0.04 (SMC-like extinction) at 99% confidence (3 sigma), assuming that E(B-V) is the same for all DLAs. Finally, we do not find any general correlation between absorber properties (such as [Fe/Zn] or neutral hydrogen column density) and B-K color. One of these two QSOs shows evidence for strong associated absorption from X-ray observations, an alternative explanation for its very red color. We conclude that the presence of intervening galaxies causes a minimal reddening of the background QSO.

Accepted for publication in AJ

References in corpus (30)

• Interstellar Dust Grains
• Composite Quasar Spectra From the Sloan Digital Sky Survey
• Red and Reddened Quasars in the Sloan Digital Sky Survey
• The VLT-UVES survey for molecular hydrogen in high-redshift damped Lyman-alpha systems
• Dust Reddening in SDSS Quasars
• A FUSE Survey of Interstellar Molecular Hydrogen in the Small and Large Magellanic Clouds
• The host of GRB 030323 at z=3.372: a very high column density DLA system with a low metallicity
• The UCSD HIRES/KeckI Damped Lya Abundance Database: II. The Implications
• Mg II Absorption Systems in SDSS QSO Spectra
• The CORALS Survey I: New Estimates of the Number Density and Gas Content of Damped Lyman Alpha Systems Free from Dust Bias
• The Nuclear Reddening Curve for Active Galactic Nuclei and the Shape of the Infra-Red to X-Ray Spectral Energy Distribution
• Hubble Space Telescope Observations of Element Abundances in Low-redshift Damped Lyman-alpha Galaxies and Implications for the Global Metallicity-Redshift Relation
• Dust and Diffuse Interstellar Bands in the z_a = 0.524 Absorption System toward AO 0235+164
• FIRST-2MASS Sources Below the APM Detection Threshold: A Population of Highly Reddened Quasars
• Dust-reddening and gravitational lensing of SDSS QSOs due to foreground damped Lyman-alpha systems
• Detection of the 2175ÅExtinction Feature at z=0.83
• Metals and Dust in Intermediate-redshift Damped Ly-alpha Galaxies
• Detections of the 2175 ÅDust Feature at 1.4z 1.5 from the Sloan Digital Sky Survey
• Disentangling microlensing and differential extinction in the double QSO HE0512-3329
• Extinction curves expected in young galaxies
• An I-Band-Selected Sample of Radio-Emitting Quasars: Evidence for a Large Population of Red Quasars
• Evidence for dust reddening in DLAs identified through CaII H&K absorption
• The extinction law in high redshift galaxies
• The Number Density of 0.6 < z < 1.7 MgII Systems from CORALS: Observational Biases at Intermediate Redshift
• Unusual Metal Abundances in a Pair of Damped Lyman Alpha Systems at z~2
• Emission Line Abundances of Absorption Selected Galaxies at z<0.5
• Gemini-South + FLAMINGOS Demonstration Science: Near-Infrared Spectroscopy of the z=5.77 Quasar SDSS J083643.85+005453.3
• The 2dF QSO Redshift Survey - VIII. Absorption systems in the 10k catalogue
• XMM-Newton spectroscopy of high redshift quasars
• Dust obscuration studies along quasar sight lines using simulated galaxies

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