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arXiv · 1707.01443

The VIMOS Ultra Deep Survey: The role of HI kinematics and HI column density on the escape of Lyalpha photons in star-forming galaxies at 2<z<4

L. Guaita·M. Talia·L. Pentericci·A. Verhamme·P. Cassata·B. C. Lemaux·I. Orlitova·B. Ribeiro·D. Schaerer·G. Zamorani·B. Garilli·V. Le Brun·O. Le Fevre·D. Maccagni·L. A. M. Tasca·R. Thomas·E. Vanzella·E. Zucca·R. Amorin·S. Bardelli·M. Castellano·A. Grazian·N. P. Hathi·A. Koekemoer·F. Marchi
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Abstract

We selected a sample of 76 Lya emitting galaxies from the VIMOS Ultra Deep Survey (VUDS) at 2 300km/sec. An ISM with this value of NHI would favour a large amount of scattering events, especially when the medium is static, so it can explain large values of Ext(Lya-C) and small EW(Lya). On the contrary, an ISM with a lower NHI, but large velocity outflows would lead to a Lya spatial profile peaked at the galaxy center (i.e. low values of Ext(Lya-C)) and to a large EW(Lya), as we see in our data. Our results and their interpretation via radiative-transfer models tell us that it is possible to use Lya to study the properties of the HI gas.

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L. Guaita, M. Talia, L. Pentericci, A. Verhamme, P. Cassata, B. C. Lemaux, I. Orlitova, B. Ribeiro, D. Schaerer, G. Zamorani, B. Garilli, V. Le Brun, O. Le Fevre, D. Maccagni, L. A. M. Tasca, R. Thomas, E. Vanzella, E. Zucca, R. Amorin, S. Bardelli, M. Castellano, A. Grazian, N. P. Hathi, A. Koekemoer, F. Marchi. 2017-07-05. The VIMOS Ultra Deep Survey: The role of HI kinematics and HI column density on the escape of Lyalpha photons in star-forming galaxies at 2<z<4. https://doi.org/10.1051/0004-6361/201730603

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