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arXiv · 1709.00991

The MUSE-Wide survey: A measurement of the Ly$\alpha$ emitting fraction among $z>3$ galaxies

Joseph Caruana·Lutz Wisotzki·Edmund Christian Herenz·Josephine Kerutt·Tanya Urrutia·Kasper Borello Schmidt·Rychard Bouwens·Jarle Brinchmann·Sebastiano Cantalupo·Marcella Carollo·Catrina Diener·Alyssa Drake·Thibault Garel·Raffaella Anna Marino·Johan Richard·Rikke Saust·Joop Schaye·Anne Verhamme
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Abstract

We present a measurement of the fraction of Lyman $\alpha$ (Ly$\alpha$) emitters ($X_{\rm{Ly} \alpha}$) amongst HST continuum-selected galaxies at $3<z<6$ with the Multi-Unit Spectroscopic Explorer (MUSE) on the VLT. Making use of the first 24 MUSE-Wide pointings in GOODS-South, each having an integration time of 1 hour, we detect 100 Ly$\alpha$ emitters and find $X_{\rm{Ly} \alpha}\gtrsim0.5$ for most of the redshift range covered, with 29 per cent of the Ly$\alpha$ sample exhibiting rest equivalent widths (rest-EWs) $\leq$ 15\AA. Adopting a range of rest-EW cuts (0 - 75\AA), we find no evidence of a dependence of $X_{\rm{Ly} \alpha}$ on either redshift or UV luminosity.

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Joseph Caruana, Lutz Wisotzki, Edmund Christian Herenz, Josephine Kerutt, Tanya Urrutia, Kasper Borello Schmidt, Rychard Bouwens, Jarle Brinchmann, Sebastiano Cantalupo, Marcella Carollo, Catrina Diener, Alyssa Drake, Thibault Garel, Raffaella Anna Marino, Johan Richard, Rikke Saust, Joop Schaye, Anne Verhamme. 2017-09-04. The MUSE-Wide survey: A measurement of the Ly$\alpha$ emitting fraction among $z>3$ galaxies. https://doi.org/10.1093/mnras%2Fstx2307

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