H. Beuther, J. Tackenberg, H. Linz, Th. Henning, F. Schuller, F. Wyrowski, P. Schilke, K. Menten, T. P. Robitaille, C. M. Walmsley, L. Bronfman, F. Motte, Q. Nguyen-Luong, S. Bontemps
The ATLASGAL 870mum continuum survey conducted with the APEX telescope is the
first survey covering the whole inner Galactic plane (60deg>l>-60deg &
b<1.5deg) in submm continuum emission tracing the cold dust of dense and young
star-forming regions. Here, we present the overall distribution of sources
within our Galactic disk. The submm continuum emission is confined to a narrow
range around the galactic plane, but shifted on average by ~0.07deg below the
plane. Source number counts show strong enhancements toward the Galactic
center, the spiral arms and toward prominent star-forming regions. Comparing
the distribution of ATLASGAL dust continuum emission to that of young
intermediate- to high-mass young stellar objects (YSOs) derived from Spitzer
data, we find similarities as well as differences. In particular, the
distribution of submm dust continuum emission is significantly more confined to
the plane than the YSO distribution (FWHM of 0.7 and 1.1deg, corresponding to
mean physical scale heights of approximately 46 and 80pc, respectively). While
this difference may partly be caused by the large extinction from the dense
submm cores, gradual dispersal of stellar distributions after their birth could
also contribute to this effect. Compared to other tracers of Galactic
structure, the ATLASGAL data are strongly confined to a narrow latitude strip
around the Galactic plane.
View original:
http://arxiv.org/abs/1112.4609
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