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Description
We present integral field spectroscopic observations with the Potsdam Multi-Aperture Spectrophotometer of all 14 galaxies in the z~0.1 Lyman Alpha Reference Sample (LARS). We produce 2D line-of-sight velocity maps and velocity dispersion maps from the Balmer {alpha} (H{alpha}) emission in our data cubes. These maps trace the spectral and spatial properties of the LARS galaxies' intrinsic Ly{alpha} radiation field. We show our kinematic maps that are spatially registered onto the Hubble Space Telescope H{alpha} and Lyman{alpha} (Ly{alpha}) images. We can conjecture a causal connection between spatially resolved H{alpha} kinematics and Ly{alpha} photometry for individual galaxies. However, no general trend can be established for the whole sample. Furthermore, we compute the intrinsic velocity dispersion {sigma}_0_, the shearing velocity v_shear_, and the v_shear_/{sigma}_0_ ratio from our kinematic maps. In general LARS galaxies are characterised by high intrinsic velocity dispersions (54km/s median) and low shearing velocities (65km/s median). The v_shear_/{sigma}_0_ values range from 0.5 to 3.2 with an average of 1.5. It is noteworthy that five galaxies of the sample are dispersion-dominated systems with v_shear_/{sigma}_0_<1, and are thus kinematically similar to turbulent star-forming galaxies seen at high redshift. When linking our kinematical statistics to the global LARS Ly{alpha} properties, we find that dispersion-dominated systems show higher Ly{alpha} equivalent widths and higher Ly{alpha} escape fractions than systems with v_shear_/{sigma}_0_>1. Our result indicates that turbulence in actively star-forming systems is causally connected to interstellar medium conditions that favour an escape of Ly{alpha} radiation.
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