The Astrophysical Journal (Jan 2023)
Optimized Photometric Redshifts for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS)
- Dritan Kodra,
- Brett H. Andrews,
- Jeffrey A. Newman,
- Steven L. Finkelstein,
- Adriano Fontana,
- Nimish Hathi,
- Mara Salvato,
- Tommy Wiklind,
- Stijn Wuyts,
- Adam Broussard,
- Nima Chartab,
- Christopher Conselice,
- M. C. Cooper,
- Avishai Dekel,
- Mark Dickinson,
- Henry C. Ferguson,
- Eric Gawiser,
- Norman A. Grogin,
- Kartheik Iyer,
- Jeyhan Kartaltepe,
- Susan Kassin,
- Anton M. Koekemoer,
- David C. Koo,
- Ray A. Lucas,
- Kameswara Bharadwaj Mantha,
- Daniel H. McIntosh,
- Bahram Mobasher,
- Camilla Pacifici,
- Pablo G. Pérez-González,
- Paola Santini
Affiliations
- Dritan Kodra
- Department of Physics and Astronomy, University of Pittsburgh , Pittsburgh, PA 15260, USA ; [email protected]; Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT PACC), University of Pittsburgh , Pittsburgh, PA 15260, USA
- Brett H. Andrews
- ORCiD
- Department of Physics and Astronomy, University of Pittsburgh , Pittsburgh, PA 15260, USA ; [email protected]; Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT PACC), University of Pittsburgh , Pittsburgh, PA 15260, USA
- Jeffrey A. Newman
- ORCiD
- Department of Physics and Astronomy, University of Pittsburgh , Pittsburgh, PA 15260, USA ; [email protected]; Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT PACC), University of Pittsburgh , Pittsburgh, PA 15260, USA
- Steven L. Finkelstein
- ORCiD
- Department of Astronomy, The University of Texas at Austin , 2515 Speedway, Austin, TX 78712, USA
- Adriano Fontana
- ORCiD
- Osservatorio Astronomico di Roma , via di Frascati 33, I-00078 Monte Porzio Catone (Roma), Italy
- Nimish Hathi
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Mara Salvato
- ORCiD
- Max-Planck-Institut für extraterrestrische Physik , Giessenbachstr. 1, D-85748 Garching, Germany
- Tommy Wiklind
- ORCiD
- Department of Physics, Catholic University of America , Washington DC 20064, USA
- Stijn Wuyts
- ORCiD
- Department of Physics, University of Bath , Claverton Down, Bath BA2 7AY, UK
- Adam Broussard
- ORCiD
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey , Piscataway, NJ 08854, USA
- Nima Chartab
- ORCiD
- Department of Physics and Astronomy, University of California , Irvine, CA 92697, USA
- Christopher Conselice
- ORCiD
- Jodrell Bank Centre for Astrophysics, University of Manchester , Oxford Road, Manchester, UK
- M. C. Cooper
- ORCiD
- Center for Cosmology, Department of Physics & Astronomy, University of California , Irvine, 4129 Reines Hall, Irvine, CA 92697, USA
- Avishai Dekel
- ORCiD
- Racah Institute of Physics, The Hebrew University , Jerusalem 91904, Israel
- Mark Dickinson
- ORCiD
- NSF’s NOIRLab, 950 N. Cherry Avenue, Tucson, AZ 85719, USA
- Henry C. Ferguson
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Eric Gawiser
- ORCiD
- Department of Physics and Astronomy, Rutgers, the State University of New Jersey , Piscataway, NJ 08854, USA
- Norman A. Grogin
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Kartheik Iyer
- ORCiD
- Dunlap Institute for Astronomy and Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Jeyhan Kartaltepe
- ORCiD
- School of Physics and Astronomy, Rochester Institute of Technology , Rochester, NY 14623, USA
- Susan Kassin
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; The William H. Miller III Department of Physics & Astronomy, Johns Hopkins University , 3400 N. Charles Street, Baltimore, MD 21218, USA
- Anton M. Koekemoer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- David C. Koo
- ORCiD
- Department of Astronomy and Astrophysics, University of California , Santa Cruz, Santa Cruz, CA 95064, USA
- Ray A. Lucas
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Kameswara Bharadwaj Mantha
- Minnesota Institute for Astrophysics, University of Minnesota , 116 Church Street SE, Minneapolis, MN 55455, USA; School of Physics and Astronomy, University of Minnesota , 116 Church Street SE, Minneapolis, MN 55455, USA
- Daniel H. McIntosh
- Department of Physics & Astronomy, University of Missouri , Kansas City, Kansas City, MO 64110, USA
- Bahram Mobasher
- Department of Physics and Astronomy, University of California , Riverside, 900 University Avenue, Riverside, CA 92521, USA
- Camilla Pacifici
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Pablo G. Pérez-González
- ORCiD
- Centro de Astrobiología, CAB/CSIC-INTA, Ctra. de Torrejón a Ajalvir, km 4, E-28850, Torrejón de Ardoz, Madrid, Spain
- Paola Santini
- ORCiD
- Osservatorio Astronomico di Roma , via di Frascati 33, I-00078 Monte Porzio Catone (Roma), Italy
- DOI
- https://doi.org/10.3847/1538-4357/ac9f12
- Journal volume & issue
-
Vol. 942,
no. 1
p. 36
Abstract
We present the first comprehensive release of photometric redshifts (photo - z 's) from the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) team. We use statistics based upon the Quantile–Quantile ( Q – Q ) plot to identify biases and signatures of underestimated or overestimated errors in photo - z probability density functions (PDFs) produced by six groups in the collaboration; correcting for these effects makes the resulting PDFs better match the statistical definition of a PDF. After correcting each group’s PDF, we explore three methods of combining the different groups’ PDFs for a given object into a consensus curve. Two of these methods are based on identifying the minimum f -divergence curve, i.e., the PDF that is closest in aggregate to the other PDFs in a set (analogous to the median of an array of numbers). We demonstrate that these techniques yield improved results using sets of spectroscopic redshifts independent of those used to optimize PDF modifications. The best photo - z PDFs and point estimates are achieved with the minimum f -divergence using the best four PDFs for each object (mFDa4) and the hierarchical Bayesian (HB4) methods, respectively. The HB4 photo - z point estimates produced σ _NMAD = 0.0227/0.0189 and ∣Δ z /(1 + z )∣ > 0.15 outlier fraction = 0.067/0.019 for spectroscopic and 3D Hubble Space Telescope redshifts, respectively. Finally, we describe the structure and provide guidance for the use of the CANDELS photo - z catalogs, which are available at https://archive.stsci.edu/prepds/candels/ .
Keywords
