A Wide-area VLA Continuum Survey near the Galactic Center at 6 and 20 cm Wavelengths

Abstract

We describe the results of a mJy-sensitivity, VLA survey of roughly 1 square degree near the Galactic center at 6 and 20 cm. Catalogs of compact and filamentary structures are given and compared to previous surveys of the region. Eight of the unusual, nonthermal radio filaments are detected in 6 cm polarized emission; three of these are the first such detections, confirming their nonthermal nature. This survey found emission from a filament at (l,b)=(359.1,0.75), or a projected distance from Sgr A* of 200 pc, greatly extending the latitude range observed with such features. There is also new evidence for spatial gradients in the 6/20 cm spectral indices of some filaments and we discuss models for these gradients. In studying compact sources, the combination of spectral index and polarization information allows us to identify pulsar candidates and compact HII regions in the survey. There is also some evidence that the flux measurements of compact sources may be affected by electron scattering from the interstellar medium in the cent ral few hundred parsecs of the Galaxy.

arXiv commentAccepted to ApJS. Uses emulateapj style with 47 pages, 29 figures, and 13 tables

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Cited by in corpus (30)

• The 1.28 GHz MeerKAT Galactic Center Mosaic
• Subarcsecond international LOFAR radio images of the M82 nucleus at 118 MHz and 154 MHz
• Dark Matter and Synchrotron Emission from Galactic Center Radio Filaments
• Probing Cosmic Ray Transport with Radio Synchrotron Harps in the Galactic Center
• Statistical Properties of the Population of the Galactic Center Filaments: The Spectral Index and Equipartition Magnetic Field
• A 6.7 GHz Methanol Maser Survey II. Low Galactic Latitudes
• A Multiwavelength View of a Mass Outflow from the Galactic Center
• The physical and chemical structure of Sagittarius B2 -- V. Non-thermal emission in the envelope of Sgr B2
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• Fourier Plane Image Combination by Feathering
• A Constraint on the Organization of the Galactic Center Magnetic Field Using Faraday Rotation
• Constraining the Evolutionary Fate of Central Compact Objects: "Old" Radio Pulsars in Supernova Remnants
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• The physical and chemical structure of Sagittarius B2 -- VI. UCHII regions in Sgr B2
• A novel analytical model of the magnetic field configuration in the Galactic Center
• Discovery of possible molecular counterparts to the infrared Double Helix Nebula in the Galactic center
• A 6.7 GHz methanol maser survey of the central molecular zone
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• Understanding the Geometry of Astrophysical Magnetic Fields
• Statistical Properties of the Population of the Galactic Center Filaments II: The Spacing Between Filaments
• Swift follow-up observations of unclassified ASCA sources
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• Detailed molecular observations toward the Double Helix Nebula
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• The connecting molecular ridge in the Galactic center
• The SARAO MeerKAT Galactic Plane Survey filamentary source catalogue