The Atacama Cosmology Telescope: Microwave Intensity and Polarization Maps of the Galactic Center

Abstract

We present arcminute-resolution intensity and polarization maps of the Galactic center made with the Atacama Cosmology Telescope (ACT). The maps cover a 32 deg${}^2$ field at 98, 150, and 224 GHz with $|l|\le 4^{\circ }$, $|b|\le 2^{\circ }$. We combine these data with Planck observations at similar frequencies to create coadded maps with increased sensitivity at large angular scales. With the coadded maps, we are able to resolve many known features of the Central Molecular Zone (CMZ) in both total intensity and polarization. We map the orientation of the plane-of-sky component of the Galactic magnetic field inferred from the polarization angle in the CMZ, finding significant changes in morphology in the three frequency bands as the underlying dominant emission mechanism changes from synchrotron to dust emission. Selected Galactic center sources, including Sgr A*, the Brick molecular cloud (G0.253+0.016), the Mouse pulsar wind nebula (G359.23-0.82), and the Tornado supernova remnant candidate (G357.7-0.1), are examined in detail. These data illustrate the potential for leveraging ground-based Cosmic Microwave Background polarization experiments for Galactic science.

26 pages, 14 figures, accepted for publication in ApJ

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Cited by in corpus (16)

• The Simons Observatory: Galactic Science Goals and Forecasts
• Magnetic field morphology and evolution in the Central Molecular Zone and its effect on gas dynamics
• SOFIA/HAWC+ Far-InfraRed Polarimetric Large Area CMZ Exploration (FIREPLACE) Survey I: General Results from the Pilot Program
• Full-sky Models of Galactic Microwave Emission and Polarization at Sub-arcminute Scales for the Python Sky Model
• SOFIA/HAWC+ Far-Infrared Polarimetric Large-Area CMZ Exploration (FIREPLACE) Survey III: Full Survey Data Set
• Tracing the Milky Way's Vestigial Nuclear Jet
• Probing Three-Dimensional Magnetic Fields: I -- Polarized Dust Emission
• Pulsar-wind-nebula-powered Galactic center X-ray filament G0.13-0.11: Proof of the synchrotron nature by IXPE
• Analyzing the Intrinsic Magnetic Field in the Galactic Center Radio Arc
• On Far-Infrared and Submm Circular Polarization
• Evidence for an interaction between the Galactic Center clouds M0.10-0.08 and M0.11-0.11
• The JWST-NIRCam View of Sagittarius C. II. Evidence for Magnetically Dominated HII Regions in the CMZ
• SOFIA/HAWC+ Far-Infrared Polarimetric Large Area CMZ Exploration Survey. V. The Magnetic Field Strength and Morphology in the Sagittarius C Complex
• Performance of the polarization leakage correction in the PILOT data
• The SARAO MeerKAT Galactic Plane Survey filamentary source catalogue
• The Complex Magnetic Field of the Extreme Galactic Center: PRIMA Science Potential