Investigating the source of Planck-detected AME: high resolution observations at 15 GHz

TL;DR

This study uses high-resolution 15 GHz observations to investigate the presence and characteristics of anomalous microwave emission in specific regions identified by Planck, confirming some cases of spinning dust emission and ruling out others.

Contribution

It provides new high-resolution data at 15 GHz for regions with potential AME, clarifying the presence of compact AME components and testing spinning dust models.

Findings

Detected AME-like spectrum in one region consistent with spinning dust.

No evidence of AME on small scales in the second region.

Supports the idea that AME can originate from compact or extended sources.

Abstract

The Planck 28.5 GHz maps were searched for potential Anomalous Microwave Emission (AME) regions on the scale of $\sim3^{\circ}$ or smaller, and several new regions of interest were selected. Ancillary data at both lower and higher frequencies were used to construct spectral energy distributions (SEDs), which seem to confirm an excess consistent with spinning dust models. Here we present higher resolution observations of two of these new regions with the Arcminute Microkelvin Imager Small Array (AMI SA) between 14 and 18 GHz to test for the presence of a compact ($\sim$10 arcmin or smaller) component. For AME-G107.1+5.2, dominated by the {\sc Hii} region S140, we find evidence for the characteristic rising spectrum associated with the either the spinning dust mechanism for AME or an ultra/hyper-compact \textsc{Hii} region across the AMI frequency band, however for AME-G173.6+2.8 we find no evidence for AME on scales of $\sim 2-10$ arcmin.