Description
Recent high-resolution HI observations of M33 reveal a large number of regions that are devoid of emission. We interpret these regions as holes formed by interstellar winds; a catalogue containing 148 of these HI holes has been compiled. Their diameters range from the survey resolution limit (>40pc) to 1kpc. The swept-up mass, estimated from surrounding HI densities, ranges from 10^3^M_{sun}_ to 10^7^M_{sun}_. Energies needed to excavate such holes are between 10^49^ to 10^54^erg. Indicative ages, based on derived expansion velocities and diameters, show a cutoff near 7x10^6^yr. Three statistical analysis techniques are applied to determine positional correlation of the H I holes with H II regions, OB associations, and supernova remnants.
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