Characterizing filaments in regions of high-mass star formation:
  High-resolution submilimeter imaging of the massive star-forming complex NGC
  6334 with ArT\'eMiS
  Herschel observations of nearby molecular clouds suggest that interstellar
filaments and prestellar cores represent two fundamental steps in the star
formation process. The observations support a picture of low-mass star
formation according to which ~ 0.1 pc-wide filaments form first in the cold
interstellar medium, probably as a result of large-scale compression of
interstellar matter by supersonic turbulent flows, and then prestellar cores
arise from gravitational fragmentation of the densest filaments. Whether this
scenario also applies to regions of high-mass star formation is an open
question, in part because Herschel data cannot resolve the inner width of
filaments in the nearest regions of massive star formation.
  We used the bolometer camera ArTeMiS on the APEX telescope to map the central
part of the NGC6334 complex at a factor of > 3 higher resolution than Herschel
at 350 microns. Combining ArTeMiS data with Herschel data allowed us to study
the structure of the main filament of the complex with a resolution of 8" or <
0.07 pc at d ~ 1.7 kpc.
  Our study confirms that this filament is a very dense, massive linear
structure with a line mass ranging from ~ 500 Msun/pc to ~ 2000 Msun/pc over
nearly 10 pc. It also demonstrates that its inner width remains as narrow as W
~ 0.15 +- 0.05 pc all along the filament length, within a factor of < 2 of the
characteristic 0.1 pc value found with Herschel for lower-mass filaments in the
Gould Belt. While it is not completely clear whether the NGC 6334 filament will
form massive stars or not in the future, it is two to three orders of magnitude
denser than the majority of filaments observed in Gould Belt clouds, and yet
has a very similar inner width. This points to a common physical mechanism for
setting the filament width and suggests that some important structural
properties of nearby clouds also hold in high-mass star forming regions.
