Extending the Nearby Galaxy Heritage with WISE: First Results from the WISE Enhanced Resolution Galaxy Atlas (1210.3628v2)

Abstract: The Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at mid-infrared wavelengths 3.4, 4.6, 12 and 22 microns. The mission was primarily designed to extract point sources, leaving resolved and extended sources unexplored. We have begun a dedicated WISE Enhanced Resolution Galaxy Atlas (WERGA) project to fully characterize large, nearby galaxies and produce a legacy image atlas and source catalogue. Here we demonstrate the first results of the project for a sample of 17 galaxies, chosen to be of large angular size, diverse morphology, color, stellar mass and star formation. It includes many well-studied galaxies, such as M51, M81, M83, M87, M101, IC342. Photometry and surface brightness decomposition is carried out after special super-resolution processing, achieving spatial fidelity similar to that of Spitzer-IRAC. We present WISE, Spitzer and GALEX photometric and characterization measurements, combining the measurements to study the global properties. We derive star formation rates using the PAH-sensitive 12 micron (W3) fluxes, warm-dust sensitive 22 micron (W4) fluxes, and young massive-star sensitive UV fluxes. Stellar masses are estimated using the 3.4 micron (W1) and 4.6 micron (W2) measurements that trace the dominant stellar mass content. We highlight and showcase the detailed results of M83, comparing the infrared results with the ATCA HI gas distribution and GALEX UV emission, tracing the evolution from gas to stars. In addition to the enhanced images, WISE all-sky coverage provides a tremendous advantage over Spitzer for building a complete nearby galaxy catalog, tracing both stellar mass and star formation histories. We discuss the construction of a complete mid-infrared catalog of galaxies and its complementary role to study the assembly and evolution of galaxies in the local universe.

• The paper employs the Maximum Correlation Method to achieve spatial resolutions comparable to Spitzer imaging.
• It integrates WISE, Spitzer, and GALEX data to measure star formation rates and stellar mass distributions with precision.
• The detailed study of galaxy M83 validates enhanced WISE imaging techniques, offering new insights into interstellar processes and galaxy evolution.

Extending the Nearby Galaxy Heritage with WISE: A Detailed Study of the WISE Enhanced Resolution Galaxy Atlas

The paper detailing the WISE Enhanced Resolution Galaxy Atlas (WERGA) provides a comprehensive analysis of the WISE mission's potential in characterizing nearby galaxies. This paper represents a part of a series that aims to explore the utility of the Wide-field Infrared Survey Explorer (WISE) by focusing on spatial resolution enhancements and integrating broad spectral data from complementary missions such as Spitzer and GALEX.

The paper begins by underlining the role of WISE's all-sky infrared survey as instrumental in studying the mid-infrared characteristics of nearby galaxies. Originally designed for point source extraction, WISE's capability for capturing resolved and extended sources has been significantly underutilized. The authors emphasize that by using advanced image-processing techniques such as the Maximum Correlation Method (MCM), WISE images can achieve spatial resolutions akin to those obtained through Spitzer-IRAC observations. This spatial enhancement unlocks the potential of WISE data to paper the morphology, stellar mass distribution, and star formation activities with greater precision.

The methodology involves processing galaxies with bright and contrasting features, including various morphological and star-formational properties. The authors conducted detailed photometry for selected galaxies by integrating WISE measurements with Spitzer and GALEX data, emphasizing the photometric precision achievable with enhanced image resolutions. The paper highlights the accuracy of WISE in determining star formation rates (SFRs) using 12 μm (W3) and 22 μm (W4) fluxes, underlining that such measurements are invaluable for assessing star-formation history and current galactic conditions.

A noteworthy segment of the paper is the deep analysis of the galaxy M83. Through comparing WISE and Spitzer data with ATCA Hi gas distribution and GALEX UV emission profiles, the authors illustrate a detailed assessment of the interstellar processes and star formation activities. This comparison showcases the value of WISE in resolving discrepancies and expanding on the datasets acquired from other missions, providing a nuanced look at the complex relationship between gas, dust, and star evolution.

Crucially, the paper discusses the construction of the WERGA as a comprehensive mid-infrared catalog that complements existing galaxy surveys, offering insights into the stellar mass and star formation across a wide range of environments and evolutionary stages. The authors underscore the role of WISE’s extensive coverage in creating a rich dataset that addresses key questions about galaxy formation and evolution.

In conclusion, the research underscores the essential role that enhanced WISE data can play in bridging observational gaps in extragalactic astronomy. As computational techniques continue to evolve, the integration of WISE with higher-resolution datasets could lead to more profound discoveries about galaxy assembly dynamics and the influence of various energy and matter components within galaxies. Future research will likely build on these foundational insights to explore further the assembly and evolution of galaxies across the local universe.