We compare the Hβ line strengths of 1.90 z 2.35 star-forming galaxies observed with the near-IR grism of the Hubble Space Telescope with ground-based measurements of Lyα from the HETDEX Pilot Survey and narrow-band imaging. By examining the line ratios of 73 galaxies, we show that most star-forming systems at this epoch have a Lyα escape fraction below ~6%. We confirm this result by using stellar reddening to estimate the effective logarithmic extinction of the Hβ emission line (c Hβ = 0.5) and measuring both the Hβ and Lyα luminosity functions in a ~100, 000?Mpc3 volume of space. We show that in our redshift window, the volumetric Lyα escape fraction is at most , with an additional systematic ~25% uncertainty associated with our estimate of extinction. Finally, we demonstrate that the bulk of the epoch's star-forming galaxies have Lyα emission line optical depths that are significantly greater than that for the underlying UV continuum. In our predominantly [O III] λ5007-selected sample of galaxies, resonant scattering must be important for the escape of Lyα photons.
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