Published online by Cambridge University Press: 26 May 2016
The fragmentation of supershells and filaments driven by a superwind in a starburst region produces clumps with a mass spectrum approximated by a power law. Its spectral index is close to −2.3. We present results of computer simulations using the thin shell approximation, which are compared to 3D hydrodynamical simulations with self-gravity using the ZEUS computer code. In a low density medium the fragmentation time-scale is comparable to the collisional time-scale, and consequently collisions change the mass spectra of fragments to less steep values. In high density environments collisional time-scales are much longer and the mass spectrum results from gravitational fragmentation of expanding sheets and filaments.