EPoS Contribution
EPoS Contribution
The observed properties of a filament system in Orion B

Doris Arzoumanian
CEA, Saclay, FR
The highly filamentary structure of the interstellar medium is now impressively revealed by Herschel and Planck images. Previous observations have shown that molecular clouds are filamentary, however, only recently have interstellar filaments received special attention, thanks to the new observational results on the properties of filaments, demonstrating their key roles in the star formation process. I will present new results on the properties of a filament system discovered by Herschel in the northern part of the Orion B molecular cloud. The Herschel images display the filamentary structures of this system, where a thermally supercritical star forming filament (prestellar and protostellar cores are observed along its length) is surrounded by lower column density filaments. In particular, a well defined thermally subcritical and quiescent filament connected to the supercritical filament from the side.These two filaments, have central column densities (and masse per unit length) that differ by more than one order of magnitude, yet they show the same inner width of 0.1 pc. I will describe the kinematics of this filament system derived from maps of molecular line observations tracing the star forming dense filament (N2H+, HCO+) and the lower column density surroundings (13CO, C18O). I will discuss what we can learn about the formation and evolution of this filament system combining the results derived from the Herschel submillimetre dust emission observations,the molecular line data and the large scale magnetic field structure obtained from Planck dust polarization observations.
Caption: Left: Column density map of the filament system in the North of the Orion B molecular cloud derived from Herschel observations. Right: Radial column density profiles perpendicular to the crests of the star-forming filament and the sub-filament.
P. Andre, CEA, FR
A. Roy, CEA, FR
Suggested Session: Filaments