A Catalog of MIPSGAL Disk and Ring Sources

TL;DR

This paper presents a catalog of 416 extended disk and ring-like objects from the MIPSGAL 24 micron survey, mainly identifying evolved stars, planetary nebulae, and some background galaxies, based on their infrared characteristics.

Contribution

It provides the first comprehensive catalog of circularly symmetric, extended objects in the Galactic plane detected at 24 microns, with classifications and potential identifications.

Findings

Most objects lack counterparts at 8 or 70 microns.

Approximately 70 objects are previously known, including emission-line stars and supernova remnants.

About 90% of the unclassified objects are likely planetary nebulae.

Abstract

We present a catalog of 416 extended, resolved, disk- and ring-like objects as detected in the MIPSGAL 24 micron survey of the Galactic plane. This catalog is the result of a search in the MIPSGAL image data for generally circularly symmetric, extended "bubbles" without prior knowledge or expectation of their physical nature. Most of the objects have no extended counterpart at 8 or 70 micron, with less than 20% detections at each wavelength. For the 54 objects with central point sources, the sources are nearly always seen in all IRAC bands. About 70 objects (16%) have been previously identified, with another 35 listed as IRAS sources. Among the identified objects, those with central sources are mostly listed as emission-line stars, but with other source types including supernova remnants, luminous blue variables, and planetary nebulae. The 57 identified objects (of 362) without central sources are nearly all PNe (~90%).which suggests that a large fraction of the 300+ unidentified objects in this category are also PNe. These identifications suggest that this is primarily a catalog of evolved stars. Also included in the catalog are two filamentary objects that are almost certainly SNRs, and ten unusual compact extended objects discovered in the search. Two of these show remarkable spiral structure at both 8 and 24 micron. These are likely background galaxies previously hidden by the intervening Galactic plane.