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0We present the results of a high resolution UV 2-D spectroscopic survey of star forming galaxies observed with HST-STIS. Our main aim was to map the Lyα profiles to learn about the gas kinematics and its relation with the escape of Lyα photons and to detect extended Lyα emission due to scattering in gaseous halos. We have combined our data with previously obtained UV spectroscopy on other three star-forming galaxies. We find that the P-Cygni profile is spatially extended, smooth and spans several kiloparsecs covering a region much larger than the starburst itself. We propose a scenario whereby an expanding supershell is generated by the interaction of the combined stellar winds and supernova ejecta from the young starbursts, with an extended low density halo. The variety of observed Lyα profiles both in our sample and in high redshift starbursts is explained as phases in the time evolution of the super-shell expanding into the disk and halo of the host galaxy. The observed shapes, widths and velocities are in excellent agreement with the super-shell scenario predictions and represent a time sequence. We confirm that among the many intrinsic parameters of a star forming region that can affect the properties of the observed Lyα profiles, velocity and density distributions of neutral gas along the line of sight are by far the dominant ones, while the amount of dust will determine the intensity of the emission line, if any.

Here we present a self-consistent stationary solution for spherically symmetric winds driven by massive star clusters under the impact of radiative cooling. We demonstrate that cooling may drastically modify the distribution of temperature if the rate of injected energy approaches a critical value. We also prove that the stationary wind solution does not exist when the energy radiated away at the star cluster center exceeds $30% of the energy deposition rate. Finally, we thoroughly discuss the expected appearance of super star cluster winds in the X-ray and visible line regimes. The three solutions found, the quasi-adiabatic, the strongly radiative wind, and the inhibited stationary solution, are then compared to the winds from the Arches cluster, the NGC 4303 central cluster, and to the supernebula in NGC 5253.

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