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تسجيل مستخدم جديدExtending the Nearby Galaxy Heritage with WISE: First Results from the WISE Enhanced Resolution Galaxy Atlas
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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.
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We report the discovery by the Wide-field Infrared Survey Explorer of the z = 2.452 source WISE J181417.29+341224.9, the first hyperluminous source found in the WISE survey. WISE 1814+3412 is also the prototype for an all-sky sample of ~1000 extremel
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