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

Abstract

We present a measurement of the fraction of Lyman $α$ (Ly$α$) emitters ($X_{\rm{Ly} α}$) 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$α$ emitters and find $X_{\rm{Ly} α}\gtrsim0.5$ for most of the redshift range covered, with 29 per cent of the Ly$α$ sample exhibiting rest equivalent widths (rest-EWs) $\leq$ 15à . Adopting a range of rest-EW cuts (0 - 75à ), we find no evidence of a dependence of $X_{\rm{Ly} α}$ on either redshift or UV luminosity.

10 pages, 5 figures (MNRAS, updated as per version in press)