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arXiv · 1603.02461

The ASTRODEEP Frontier Fields Catalogues: II - Photometric redshifts and rest-frame properties in Abell-2744 and MACS-J0416

M. Castellano·R. Amorín·E. Merlin·A. Fontana·R. J. McLure·E. Mármol-Queraltó·A. Mortlock·S. Parsa·J. S. Dunlop·D. Elbaz·I. Balestra·A. Boucaud·N. Bourne·K. Boutsia·G. Brammer·V. A. Bruce·F. Buitrago·P. Capak·N. Cappelluti·L. Ciesla·A. Comastri·F. Cullen·S. Derriere·S. M. Faber·E. Giallongo·A. Grazian·C. Grillo·A. Mercurio·M. J. Michałowski·M. Nonino·D. Paris·L. Pentericci·S. Pilo·P. Rosati·P. Santini·C. Schreiber·X. Shu·T. Wang
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Abstract

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. We exploit a multi-wavelength catalogue ranging from 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 multi-band 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. We show that photometric redshifts reach a remarkable ~3-5% accuracy. After accounting for magnification the H band number counts are found in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies intrinsically as faint as H160~32-33 thanks to strong gravitational lensing. The Frontier Fields allow to probe the galaxy stellar mass distribution at 0.5-1.5 dex lower masses, depending on magnification, with respect to extragalactic wide fields, including sources at Mstar~ 10^7-10^8 Msun at z>5. Similarly, they allow the detection of objects with intrinsic SFRs>1dex lower than in the CANDELS fields reaching 0.1-1 Msun/yr at z~6-10. [abridged]

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M. Castellano, R. Amorín, E. Merlin, A. Fontana, R. J. McLure, E. Mármol-Queraltó, A. Mortlock, S. Parsa, J. S. Dunlop, D. Elbaz, I. Balestra, A. Boucaud, N. Bourne, K. Boutsia, G. Brammer, V. A. Bruce, F. Buitrago, P. Capak, N. Cappelluti, L. Ciesla, A. Comastri, F. Cullen, S. Derriere, S. M. Faber, E. Giallongo, A. Grazian, C. Grillo, A. Mercurio, M. J. Michałowski, M. Nonino, D. Paris, L. Pentericci, S. Pilo, P. Rosati, P. Santini, C. Schreiber, X. Shu, T. Wang. 2016-03-08. The ASTRODEEP Frontier Fields Catalogues: II - Photometric redshifts and rest-frame properties in Abell-2744 and MACS-J0416. https://doi.org/10.1051/0004-6361/201527514

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