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arXiv · 1507.07939

SHARDS: A global view of the star formation activity at z~0.84 and z~1.23

Abstract

In this paper, we present a comprehensive analysis of star-forming galaxies (SFGs) at intermediate redshifts (z~1). We combine the ultra-deep optical spectro-photometric data from the Survey for High-z Absorption Red and Dead Sources (SHARDS) with deep UV-to-FIR observations in the GOODS-N field. Exploiting two of the 25 SHARDS medium-band filters, F687W17 and F823W17, we select [OII] emission line galaxies at z~0.84 and z~1.23 and characterize their physical properties. Their rest-frame equivalent widths (EW$_{\mathrm{rf}}$([OII])), line fluxes, luminosities, star formation rates (SFRs) and dust attenuation properties are investigated. The evolution of the EW$_{\mathrm{rf}}$([OII]) closely follows the SFR density evolution of the universe, with a trend of EW$_{\mathrm{rf}}$([OII])$\propto$(1+z)$^3$ up to redshift z~1, followed by a possible flattening. The SF properties of the galaxies selected on the basis of their [OII] emission are compared with complementary samples of SFGs selected by their MIR and FIR emission, and also with a general mass-selected sample of galaxies at the same redshifts. We demonstrate observationally that the UVJ diagram (or, similarly, a cut in the specific SFR) is only partially able to distinguish the quiescent galaxies from the SFGs. The SFR-M$_*$ relation is investigated for the different samples, yelding a logarithmic slope ~1, in good agreement with previous results. The dust attenuations derived from different SFR indicators (UV(1600), UV(2800), [OII], IR) are compared and show clear trends with respect to both the stellar mass and total SFR, with more massive and highly star-forming galaxies being affected by stronger dust attenuation.

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BibTeXRIS

Antonio Cava, Pablo G. Pérez-González, M. Carmen Eliche-Moral, Elena Ricciardelli, Alba Vidal-García, Belen Alcalde Pampliega, Almudena Alonso-Herrero, Guillermo Barro, Nicolas Cardiel, A. Javier Cenarro, Stephane Charlot, Emanuele Daddi, Miroslava Dessauges-Zavadsky, Helena Domínguez Sánchez, Nestor Espino-Briones, Pilar Esquej, Jesus Gallego, Antonio Hernán-Caballero, Marc Huertas-Company, Anton M. Koekemoer, Casiana Muñoz-Tunon, Jose M. Rodriguez-Espinosa, Lucia Rodríguez-Muñoz, Laurence Tresse, Victor Villar. 2015-10-21. SHARDS: A global view of the star formation activity at z~0.84 and z~1.23. https://doi.org/10.1088/0004-637x%2F812%2F2%2F155

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