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arXiv · 1503.01753

The VIMOS Ultra Deep Survey: Ly$\alpha$ Emission and Stellar Populations of Star-Forming Galaxies at 2<z<2.5

Nimish P. Hathi·O. Le Fèvre·O. Ilbert·P. Cassata·L. A. M. Tasca·B. C. Lemaux·B. Garilli·V. Le Brun·D. Maccagni·L. Pentericci·R. Thomas·E. Vanzella·G. Zamorani·E. Zucca·R. Amorín·S. Bardelli·L. P. Cassarà·M. Castellano·A. Cimatti·O. Cucciati·A. Durkalec·A. Fontana·M. Giavalisco·A. Grazian·L. Guaita·A. Koekemoer·S. Paltani·J. Pforr·B. Ribeiro·D. Schaerer·M. Scodeggio·V. Sommariva·M. Talia·L. Tresse·D. Vergani·P. Capak·S. Charlot·T. Contini·J. G. Cuby·S. de la Torre·J. Dunlop·S. Fotopoulou·C. López-Sanjuan·Y. Mellier·M. Salvato·N. Scoville·Y. Taniguchi·P. W. Wang
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Abstract

The aim of this paper is to investigate spectral and photometric properties of 854 faint ($i_{AB}$<~25 mag) star-forming galaxies (SFGs) at 2 $0\AA), and Ly$\alpha$ emitters (LAEs; EW$\ge$20\AA). The fraction of LAEs at these redshifts is $\sim$10%, which is consistent with previous observations. We compared best-fit SED-estimated stellar parameters of the SFG$_{\rm N}$, SFG$_{\rm L}$ and LAE samples. For the luminosities probed here ($\sim$L$^*$), we find that galaxies with and without Ly$\alpha$ in emission have small but significant differences in their SED-based properties. We find that LAEs have less dust, and lower star-formation rates (SFR) compared to non-LAEs. We also find that LAEs are less massive compared to non-LAEs, though the difference is smaller and less significant compared to the SFR and E$_{\rm s}$(B-V). [abridged]

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Nimish P. Hathi, O. Le Fèvre, O. Ilbert, P. Cassata, L. A. M. Tasca, B. C. Lemaux, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, R. Amorín, S. Bardelli, L. P. Cassarà, M. Castellano, A. Cimatti, O. Cucciati, A. Durkalec, A. Fontana, M. Giavalisco, A. Grazian, L. Guaita, A. Koekemoer, S. Paltani, J. Pforr, B. Ribeiro, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, L. Tresse, D. Vergani, P. Capak, S. Charlot, T. Contini, J. G. Cuby, S. de la Torre, J. Dunlop, S. Fotopoulou, C. López-Sanjuan, Y. Mellier, M. Salvato, N. Scoville, Y. Taniguchi, P. W. Wang. 2015-03-05. The VIMOS Ultra Deep Survey: Ly$\alpha$ Emission and Stellar Populations of Star-Forming Galaxies at 2<z<2.5. https://doi.org/10.1051/0004-6361%2F201526012

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