Constraints on the Polarization of the Anomalous Microwave Emission in the Perseus Molecular Complex from 7-year WMAP data

TL;DR

This study uses 7-year WMAP data to measure the intensity and constrain the polarization of anomalous microwave emission in the Perseus Molecular Complex, providing limits that challenge some existing emission models.

Contribution

It offers new polarization constraints on anomalous microwave emission using WMAP data, refining models of emission mechanisms in the Perseus region.

Findings

Upper limits on polarization at 23, 33, and 41 GHz are 1.0%, 1.8%, and 2.7%.

Results rule out some magnetic dipole emission models.

Findings are consistent with electric dipole and resonance relaxation theories.

Abstract

We have used the seven year Wilkinson Microwave Anisotropy Probe (WMAP) data in order to update the measurements of the intensity signal in the G159.6-18.5 region within the Perseus Molecular Complex, and to set constraints on the polarization level of the anomalous microwave emission in the frequency range where this emission is dominant. At 23, 33 and 41 GHz, we obtain upper limits on the fractional linear polarization of 1.0, 1.8 and 2.7% respectively (with a 95 per cent confidence level). These measurements rule out a significant number of models based on magnetic dipole emission of grains that consist of a simple domain (Draine & Lazarian 1999) as responsible of the anomalous emission. When combining our results with the measurement obtained with the COSMOSOMAS experiment at 11 GHz (Battistelli et al. 2006), we find consistency with the predictions of the electric dipole and resonance relaxation theory (Lazarian & Draine 2000) at this frequency range.