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The z=3 QSO Luminosity Function with SWIRE

B. Siana·M. Polletta·H. E. Smith·C. J. Lonsdale·E. Gonzalez-Solares·D. Farrah·T. S. R. Babbedge·M. Rowan-Robinson·J. Surace·D. Shupe·F. Fang
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Abstract

We use a simple optical/infrared photometric selection of high redshift QSOs which identifies a Lyman Break in the optical and requires a red IRAC color to distinguish QSOs from common interlopers. We find 100 U-dropout (z=3) QSO candidates with r'<22 within 11.2 deg^2 in the ELAIS-N1 & ELAIS-N2 fields in the Spitzer Wide-Area Infrared Extragalactic (SWIRE) Legacy Survey. Spectroscopy of 10 candidates shows that they are all QSOs with 2.83<z<3.44. We use detailed simulations which incorporate variations in QSO SEDs, IGM transmission and imaging depth to derive a completeness of 85-90% between 3.0<z<3.4. The resulting luminosity function is two magnitudes fainter than SDSS and, when combined with those data, gives a faint end slop β= 1.62 \pm 0.18, consistent with measurements at z<2 and steeper than initial measurements at the same redshift.

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B. Siana, M. Polletta, H. E. Smith, C. J. Lonsdale, E. Gonzalez-Solares, D. Farrah, T. S. R. Babbedge, M. Rowan-Robinson, J. Surace, D. Shupe, F. Fang. 2006-04-18. The z=3 QSO Luminosity Function with SWIRE. https://arxiv.org/abs/astro-ph/0604373

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