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The average starburst galaxy in the local universe (weighted by FIR luminosity, a convenient estimator of the star-formation rate (SFR) in all but the most metal-poor galaxies) has a FIR luminosity of LFIR ~ L* (Soifer et al. 1987) and a SFR of a few Msun yr-1 (Heckman et al. 1993). In general these galaxies are late type spiral galaxies with rotational velocities vrot ~ 200 km/s, local examples being NGC 253, NGC 3628 & NGC 4945. It is these "typical" starbursts that show most clearly evidence for starburst-driven outflows (Armus et al. 1990), and I shall mainly concentrate on discussing this class of galaxies. In terms of overall significance, approximately ~ 25% of all high mass star-formation in the the local universe is in starburst galaxies (Heckman 1998), and it is likely that all starbursts drive outflows. This is not a rare or exotic phenomenon.

Although outflows from dwarf galaxies have captured much of the theoretical effort on outflows (e.g. Mac Low & Ferrara 1999), under the assumption that it is easier to drive outflows in low mass systems, it is important to realize that this does not automatically mean that larger galaxies do not drive outflows. I will not discuss outflows from local ultraluminous IR galaxies (ULIRGs) which have SFRs up to ~ 30 times greater than the average starburst galaxy, or the starbursting systems seen at high redshift (see Pettini, this volume), except to note that they appear at least as powerful as winds in local starburst galaxies.