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arXiv · 1310.6653

TADPOL: A 1.3 mm Survey of Dust Polarization in Star-forming Cores and Regions

Abstract

We present λ1.3 mm CARMA observations of dust polarization toward 30 star-forming cores and 8 star-forming regions from the TADPOL survey. We show maps of all sources, and compare the ~2.5" resolution TADPOL maps with ~20" resolution polarization maps from single-dish submillimeter telescopes. Here we do not attempt to interpret the detailed B-field morphology of each object. Rather, we use average B-field orientations to derive conclusions in a statistical sense from the ensemble of sources, bearing in mind that these average orientations can be quite uncertain. We discuss three main findings: (1) A subset of the sources have consistent magnetic field (B-field) orientations between large (~20") and small (~2.5") scales. Those same sources also tend to have higher fractional polarizations than the sources with inconsistent large-to-small-scale fields. We interpret this to mean that in at least some cases B-fields play a role in regulating the infall of material all the way down to the ~1000 AU scales of protostellar envelopes. (2) Outflows appear to be randomly aligned with B-fields; although, in sources with low polarization fractions there is a hint that outflows are preferentially perpendicular to small-scale B-fields, which suggests that in these sources the fields have been wrapped up by envelope rotation. (3) Finally, even at ~2.5" resolution we see the so-called "polarization hole" effect, where the fractional polarization drops significantly near the total intensity peak. All data are publicly available in the electronic edition of this article.

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Charles L. H. Hull, Richard L. Plambeck, Woojin Kwon, Geoffrey C. Bower, John M. Carpenter, Richard M. Crutcher, Jason D. Fiege, Erica Franzmann, Nicholas S. Hakobian, Carl Heiles, Martin Houde, A. Meredith Hughes, James W. Lamb, Leslie W. Looney, Daniel P. Marrone, Brenda C. Matthews, Thushara Pillai, Marc W. Pound, Nurur Rahman, Göran Sandell, Ian W. Stephens, John J. Tobin, John E. Vaillancourt, N. H. Volgenau, Melvyn C. H. Wright. 2014-05-06. TADPOL: A 1.3 mm Survey of Dust Polarization in Star-forming Cores and Regions. https://doi.org/10.1088/0067-0049%2F213%2F1%2F13

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