Filaments and ridges in Vela C revealed by Herschel: from low-mass to
  high-mass star-forming sites
  We present the first Herschel PACS and SPIRE results of the Vela C molecular
complex in the far-infrared and submillimetre regimes at 70, 160, 250, 350, and
500 um, spanning the peak of emission of cold prestellar or protostellar cores.
Column density and multi-resolution analysis (MRA) differentiates the Vela C
complex into five distinct sub-regions. Each sub-region displays differences in
their column density and temperature probability distribution functions (PDFs),
in particular, the PDFs of the `Centre-Ridge' and `South-Nest' sub-regions
appear in stark contrast to each other. The Centre-Ridge displays a bimodal
temperature PDF representative of hot gas surrounding the HII region RCW 36 and
the cold neighbouring filaments, whilst the South-Nest is dominated by cold
filamentary structure. The column density PDF of the Centre-Ridge is flatter
than the South-Nest, with a high column density tail, consistent with formation
through large-scale flows, and regulation by self-gravity. At small to
intermediate scales MRA indicates the Centre-Ridge to be twice as concentrated
as the South-Nest, whilst on larger scales, a greater portion of the gas in the
South-Nest is dominated by turbulence than in the Centre-Ridge. In Vela C,
high-mass stars appear to be preferentially forming in ridges, i.e., dominant
high column density filaments.
