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arXiv · 0901.0133

A Limit on the Polarized Anomalous Microwave Emission of Lynds 1622

B. S. Mason·T. Robishaw·C. Heiles·D. Finkbeiner·C. Dickinson
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Abstract

The dark cloud Lynds 1622 is one of a few specific sites in the Galaxy where, relative to observed free-free and vibrational dust emission, there is a clear excess of microwave emission. In order to constrain models for this microwave emission, and to better establish the contribution which it might make to ongoing and near-future microwave background polarization experiments, we have used the Green Bank Telescope to search for linear polarization at 9.65 Ghz towards Lynds 1622. We place a 95.4% upper limit of 88 micro-Kelvin (123 micro-Kelvin at 99.7 confidence) on the total linear polarization of this source averaged over a 1'.3 FWHM beam. Relative to the observed level of anomalous emission in Stokes I these limits correspond to fractional linear polarizations of 2.7% and 3.5%.

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B. S. Mason, T. Robishaw, C. Heiles, D. Finkbeiner, C. Dickinson. 2009-02-12. A Limit on the Polarized Anomalous Microwave Emission of Lynds 1622. https://doi.org/10.1088/0004-637x%2F697%2F2%2F1187

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