EPoS Contribution
EPoS Contribution
An All Sky Investigation of Giant Molecular Cloud Structure

Jonathan Rowles
University of Kent, Canterbury, UK
Recent wide-field near- and mid-infrared observations have led to advances in our understanding of star formation. In giant molecular clouds star formation modes ranging widely from clustered to isolated are observed. The distribution of these modes within giant molecular clouds is certainly linked to their large scale density and velocity structure. To understand the causes for the distribution of clustered and isolated modes we investigate the column density distribution of all giant molecular clouds by means of two new all sky extinction maps created from 2MASS data: i) a constant spatial resolution and variable signal to noise Av map; ii) a constant signal to noise and variable spatial resolution Av map. This map is tailored to a 3sigma detection of one magnitude of optical extinction, the important threshold for self shielding in molecular clouds. Currently a spatial resolution in this map of about one arcminute near the Galactic Plane is achieved. Incorporation of forthcoming UKIDSS data will improve this by about a factor of three, hence allowing investigation of the column density distribution and dust properties of all nearby giant molecular clouds on scales of a few 10000AU. This will be a vital complementary tool for e.g. the upcoming sub-mm surveys with SCUBA2 (that will not pick up the low column density material) or investigations of the velocity structure using HARP-B.