The Faint End of the z=5 Quasar Luminosity Function from the CFHTLS

Abstract

We presents results from a spectroscopic survey of $z\sim 5$ quasars in the CFHT Legacy Survey (CFHTLS). Using both optical color selection and a likelihood method we select 97 candidates over an area of 105 deg${}^2$ to a limit of $i_{\mathrm{AB}}<23.2$, and 7 candidates in the range $23.2<i_{\mathrm{AB}}<23.7$ over an area of 18.5 deg${}^2$. Spectroscopic observations for 43 candidates were obtained with Gemini, MMT, and LBT, of which 37 are $z>4$ quasars. This sample extends measurements of the quasar luminosity function $\sim$1.5 mag fainter than our previous work in SDSS Stripe 82. The resulting luminosity function is in good agreement with our previous results, and suggests that the faint end slope is not steep. We perform a detailed examination of our survey completeness, particularly the impact of the Ly$\alpha$ emission assumed in our quasar spectral models, and find hints that the observed Ly$\alpha$ emission from faint $z\sim 5$ quasars is weaker than for $z\sim 3$ quasars at a similar luminosity. Our results strongly disfavor a significant contribution of faint quasars to the hydrogen-ionizing background at $z=5$.

26 pages, 17 figures, submitted to AJ

References in corpus (31)

• The NumPy array: a structure for efficient numerical computation
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• A luminous quasar at a redshift of z = 7.085
• An ultra-luminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30
• Model-independent evidence in favor of an end to reionization by z~6
• Evidence of patchy hydrogen reionization from an extreme Ly$\alpha$ trough below redshift six
• The Pan-STARRS1 distant z>5.6 quasar survey: more than 100 quasars within the first Gyr of the universe
• The Final SDSS High-Redshift Quasar Sample of 52 Quasars at z>5.7
• The evolution of massive black hole seeds
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• Fluctuations in the High-Redshift Lyman-Werner Background: Close Halo Pairs as the Origin of Supermassive Black Holes
• HeII Reionization and its Effect on the IGM
• Fe II Emission in 14 Low-Redshift Quasars: I - Observations
• Think Outside the Color Box: Probabilistic Target Selection and the SDSS-XDQSO Quasar Targeting Catalog
• Quasars at z=6: the survival of the fittest
• A Survey of z~6 Quasars in the SDSS Deep Stripe: I. a Flux-Limited Sample at z_{AB}<21
• Quasars Probing Quasars II: The Anisotropic Clustering of Optically Thick Absorbers around Quasars
• Probing the Evolution of IR Properties of z~6 Quasars: Spitzer Observations
• The Sloan Digital Sky Survey Stripe 82 Imaging Data: Depth-Optimized Co-adds Over 300 Deg^2 in Five Filters
• A survey of luminous high-redshift quasars with SDSS and WISE II. the bright end of the quasar luminosity function at z ~ 5
• Observational Signatures of High-Redshift Quasars and Local Relics of Black Hole Seeds
• Constraining the UV emissivity of AGN throughout cosmic time via X-ray surveys
• Detection of Rest-frame Optical Lines from X-shooter Spectroscopy of Weak Emission Line Quasars
• Weak Emission Line Quasars in the Context of a Modified Baldwin Effect
• Hyperaccreting black holes in galactic nuclei
• Re-examining the case for neutral gas near the redshift 7 quasar ULAS J1120+0641
• The Chandra COSMOS Legacy survey: the z>3 sample
• Close companions to two high-redshift quasars
• Extended Photometry for the DEEP2 Galaxy Redshift Survey: A Testbed for Photometric Redshift Experiments
• The line-of-sight proximity effect in individual quasar spectra
• An Optically Faint Quasar Survey at z~5 in the CFHTLS Wide Field: Estimates of the Black Hole Masses and Eddington Ratios

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