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arXiv · 1403.3693

The VIMOS Ultra-Deep Survey (VUDS): fast increase of the fraction of strong Lyman alpha emitters from z=2 to z=6

P. Cassata·L. A. M. Tasca·O. Le Fevre·B. Lemaux·B. Garilli·V. Le Brun·D. Maccagni·L. Pentericci·R. Thomas·E. Vanzella·G. Zamorani·E. Zucca·R. Amorin·S. Bardelli·P. Capak·L. Cassara'·M. Castellano·A. Cimatti·J. G. Cuby·O. Cucciati·S. de la Torre·A. Durkalec·A. Fontana·M. Giavalisco·A. Grazian·N. P. Hathi·O. Ilbert·C. Moreau·S. Paltani·B. Ribeiro·M. Salvato·D. Schaerer·M. Scodeggio·V. Sommariva·M. Talia·Y. Taniguchi·L. Tresse·D. Vergani·P. W. Wang·S. Charlot·T. Contini·S. Fotopoulou·C. Lopez-Sanjuan·Y. Mellier·N. Scoville
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Abstract

Aims. The aim of this work is to constrain the evolution of the fraction of Lya emitters among UV selected star forming galaxies at 2 25A to increase from 5% at z=2 to 30% at z=6, with the increase being relatively stronger beyond z=4. We observe no difference, for the narrow range of UV luminosities explored in this work, between the fraction of strong Lya emitters among galaxies fainter or brighter than M*, although the fraction for the FUV faint galaxies evolves faster, at 2<z<3.5, than for the bright ones. We do observe an anticorrelation between E(B-V) and fesc(Lya): generally galaxies with high fesc(Lya) have also small amounts of dust (and viceversa). However, when the dust content is low (E(B-V)<0.05) we observe a very broad range of fesc(Lya), ranging from 10^-3 to 1. This implies that the dust alone is not the only regulator of the amount of escaping Lya photons.

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P. Cassata, L. A. M. Tasca, O. Le Fevre, B. Lemaux, B. Garilli, V. Le Brun, D. Maccagni, L. Pentericci, R. Thomas, E. Vanzella, G. Zamorani, E. Zucca, R. Amorin, S. Bardelli, P. Capak, L. Cassara', M. Castellano, A. Cimatti, J. G. Cuby, O. Cucciati, S. de la Torre, A. Durkalec, A. Fontana, M. Giavalisco, A. Grazian, N. P. Hathi, O. Ilbert, C. Moreau, S. Paltani, B. Ribeiro, M. Salvato, D. Schaerer, M. Scodeggio, V. Sommariva, M. Talia, Y. Taniguchi, L. Tresse, D. Vergani, P. W. Wang, S. Charlot, T. Contini, S. Fotopoulou, C. Lopez-Sanjuan, Y. Mellier, N. Scoville. 2014-03-14. The VIMOS Ultra-Deep Survey (VUDS): fast increase of the fraction of strong Lyman alpha emitters from z=2 to z=6. https://doi.org/10.1051/0004-6361/201423824

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