The ASTRODEEP Frontier Fields catalogues

II. Photometric redshifts and rest frame properties in Abell-2744 and MACS-J0416^⋆

¹ INAF–Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monte Porzio Catone (RM), Italy
e-mail: marco.castellano@oa-roma.inaf.it
² SUPA, Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ, UK
³ Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu – CNRS – Université Paris Diderot, CEA-Saclay, pt courrier 131, 91191 Gif-sur-Yvette, France
⁴ INAF–Osservatorio Astronomico di Trieste, via G. B. Tiepolo 11, 34143 Trieste, Italy
⁵ Institut d’Astrophysique Spatiale, CNRS, UMR 8617, Univ. Paris-Sud, Université Paris-Saclay, IAS, Bât. 121, 91405 Orsay, France
⁶ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
⁷ Spitzer Science Center, 314-6 Caltech, Pasadena, CA 91125, USA
⁸ INAF–Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna, Italy
⁹ Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France
¹⁰ UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064, USA
¹¹ Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark
¹² INAF–Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy
¹³ Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, via Saragat 1, 44122 Ferrara, Italy
¹⁴ Instituto de Astrofísica e Ciências do Espaço, Universidade de Lisboa, OAL, Tapada da Ajuda, PT 1349-018 Lisbon, Portugal
¹⁵ Departamento de Fìsica, Faculdade de Ciências, Universidade de Lisboa, Edifìcio C8, Campo Grande, PT 1749-016 Lisbon, Portugal
¹⁶ Department of Physics, Anhui Normal University, Wuhu, 241000 Anhui, PR China
¹⁷ School of Astronomy and Astrophysics, Nanjing University, 210093 Nanjing, PR China
¹⁸ Sorbonne Universités, UPMC Univ. Paris 6 et CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98bis Bd Arago, 75014 Paris, France

Received: 6 October 2015
Accepted: 13 March 2016

Abstract

Aims. We present the first public release of photometric redshifts, galaxy rest frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416. The released catalogues aim to provide a reference for future investigations of extragalactic populations in these legacy fields: from lensed high-redshift galaxies to cluster members themselves.

Methods. We exploit a multiwavelength catalogue, ranging from Hubble Space Telescope (HST) to ground-based K and Spitzer IRAC, which is specifically designed to enable detection and measurement of accurate fluxes in crowded cluster regions. The multiband information is used to derive photometric redshifts and physical properties of sources detected either in the H-band image alone, or from a stack of four WFC3 bands. To minimize systematics, median photometric redshifts are assembled from six different approaches to photo-z estimates. Their reliability is assessed through a comparison with available spectroscopic samples. State-of-the-art lensing models are used to derive magnification values on an object-by-object basis by taking into account sources positions and redshifts.

Results. We show that photometric redshifts reach a remarkable ~3–5% accuracy. After accounting for magnification, the H-band number counts are found to be in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies that, intrinsically, are as faint as H ~ 32−33, thanks to strong gravitational lensing. The Frontier Fields allow the galaxy stellar mass distribution to be probed, depending on magnification, at 0.5–1.5 dex lower masses with respect to extragalactic wide fields, including sources at M_star ~ 10⁷–10⁸ M_⊙ at z > 5. Similarly, they allow the detection of objects with intrinsic star formation rates (SFRs) >1 dex lower than in the CANDELS fields reaching 0.1–1 M_⊙/yr at z ~ 6–10.