Bibcode
Fissel, L. M.; Ade, Peter A. R.; Angilè, Francesco E.; Ashton, Peter; Benton, Steven J.; Devlin, Mark J.; Dober, Bradley; Fukui, Yasuo; Galitzki, Nicholas; Gandilo, Natalie N.; Klein, Jeffrey; Korotkov, Andrei L.; Li, Zhi-Yun; Martin, Peter G.; Matthews, Tristan G.; Moncelsi, Lorenzo; Nakamura, Fumitaka; Netterfield, Calvin B.; Novak, Giles; Pascale, Enzo; Poidevin, F.; Santos, Fabio P.; Savini, Giorgio; Scott, Douglas; Shariff, Jamil A.; Diego Soler, Juan; Thomas, Nicholas E.; Tucker, Carole E.; Tucker, Gregory S.; Ward-Thompson, Derek
Bibliographical reference
The Astrophysical Journal, Volume 824, Issue 2, article id. 134, pp. (2016).
Advertised on:
6
2016
Journal
Citations
111
Refereed citations
100
Description
We present results for Vela C obtained during the 2012 flight of the
Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry. We
mapped polarized intensity across almost the entire extent of this giant
molecular cloud, in bands centered at 250, 350, and 500 μm. In this
initial paper, we show our 500 μm data smoothed to a resolution of
2.‧5 (approximately 0.5 pc). We show that the mean level of the
fractional polarization p and most of its spatial variations can be
accounted for using an empirical three-parameter power-law fit, p
\propto {{\boldsymbol{N}}}-0.45
{{\boldsymbol{S}}}-0.60, where N is the hydrogen column
density and S is the polarization-angle dispersion on 0.5 pc scales. The
decrease of p with increasing S is expected because changes in the
magnetic field direction within the cloud volume sampled by each
measurement will lead to cancellation of polarization signals. The
decrease of p with increasing N might be caused by the same effect, if
magnetic field disorder increases for high column density sightlines.
Alternatively, the intrinsic polarization efficiency of the dust grain
population might be lower for material along higher density sightlines.
We find no significant correlation between N and S. Comparison of
observed submillimeter polarization maps with synthetic polarization
maps derived from numerical simulations provides a promising method for
testing star formation theories. Realistic simulations should allow for
the possibility of variable intrinsic polarization efficiency. The
measured levels of correlation among p, N, and S provide points of
comparison between observations and simulations.