Detecting and understanding extragalactic Lyman alpha emission using integral-field spectroscopy
Integral-field spectroscopy is an observational technique that produces spatially resolved spectra over a two-dimensional field of view. In my talk I will show how integral field spectroscopic observations offer insights into Lyman alpha emission from galaxies and their surrounding gas reservoirs that play an important role in galaxy evolution. First, I will demonstrate how spatially resolved Balmer alpha observations of local starburst galaxies from the "Lyman Alpha Reference Sample" provide kinematical constraints for the Lyman alpha radiative transfer problem. I will then illustrate, how the MUSE instrument at ESOs Very Large Telescope is used in surveys for Lyman alpha emitting galaxies at high redshift. I conclude by presenting a selection of new results from those surveys concerning Lyman alpha haloes and Lyman alpha emitter luminosity functions.