Abstract
In this contribution I summarize our current knowledge of the nature and significance of starburst-driven galactic winds (``superwinds''). Superwinds are complex multiphase outflows of cool, warm, and hot gas, dust, and magnetized relativistic plasma. The observational manifestations of superwinds result from the hydrodynamical interaction between the primary energy-carrying wind fluid and the ambient interstellar medium. Superwinds are ubiquitous in galaxies in which the global star-formation rate per unit area exceeds roughly 10^-1 M[ scriptstyle sun ]yr-1 kpc^-2. This criterion is met by local starbursts and the high-z Lyman Break galaxies. Several independent datasets and techniques imply that the total mass and energy outflow rates in a superwind are comparable to the starburst's star-formation-rate and mechanical energy injection rate, respectively. Outflow speeds in interstellar matter entrained in the wind range from ~ 10^2 to 10^3 km/s, but the primary wind fluid itself may reach velocities as high as ~ 3000 km s-1. The available X-ray and far-UV (FUSE) data imply that radiative losses in superwinds are not significant. Superwinds may have established the mass-metallicity relation in ellipticals and bulges, polluted the present-day inter-galactic medium to a metallicity of ~ 10 to 30% solar, heated the inter-galactic medium, and ejected enough dust into the inter-galactic medium to have observable consequences.
