An H<scp>i</scp>Aperture Synthesis Mosaic of the Large Magellanic Cloud

Abstract

We present the results of an H I aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact Array (ATCA). The resolution of the mosaicked images is 10 (15 pc, using a distance to the LMC of 50 kpc). This mosaic, with a spatial resolution 15 times higher than that which had been previously obtained, emphasizes the turbulent and fractal structure of the ISM on the small scale, resulting from the dynamical feedback of the star formation processes with the ISM. The structure of the neutral atomic ISM in the LMC is dominated by H I filaments combined with numerous shells and holes. On the large scale, the H I disk appears to be remarkably symmetric and to have a well-organized and orderly, if somewhat complex, rotational field. The bulk of the H I resides in a disk 7.3 kpc in diameter. The mass of the disk component of the LMC is 2.5 × 109 M☉, and the upper limit to all mass within a radius of 4 kpc is ~3.5 × 109 M☉.