ANGULAR MOMENTUM FLUCTUATIONS IN THE CONVECTIVE HELIUM SHELL OF MASSIVE STARS

We find significant fluctuations of angular momentum within the convective helium shell of a pre-collapse massive star-a core-collapse supernova progenitor-that may facilitate the formation of accretion disks and jets that can explode the star. The convective flow in our model of an evolved M-ZAMS = 15M(circle dot) star, computed using the subsonic hydrodynamic solver MAESTRO, contains entire shells with net angular momentum in different directions. This phenomenon may have important implications for the late evolutionary stages of massive stars. and for the dynamics of core. collapse.