The Local Volume Hi Survey (LVHIS)

摘要

The 'Local Volume H I Survey' (LVHIS)1 is a large project com-prising deep interferometric HI line and 20-cm radio continuum observations of all nearby, gas-rich galaxies and their surroundings. For each galaxy we study it s gas distribution and kinematics as well as its global and local star forma-tion properties. We explore how galaxy properties (such as diameter, mass, star formation rate and mass-to-light ratio) behave as a function of environment, from the most isolated galaxies to the centres of galaxy groups. Complementary surveys of the galaxies' Hα, UV, IR and CO properties are invaluable for the project. — As examples we briefly discuss (a) the relatively isolated galaxies ES0215-G?009 and ES0223-G009, both of which have extended H i envelopes but display very different kinematics in their outer disks, and (b) the large spiral galaxy M83 which has a very large, asymmetric H i disk and tidal arm, while being surrounded by a large number of dwarf galaxies.