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A z=0 Multi-wavelength Galaxy Synthesis I: A WISE and GALEX Atlas of Local Galaxies

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 نشر من قبل Adam Leroy
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present an atlas of ultraviolet and infrared images of ~15,750 local (d < 50 Mpc) galaxies, as observed by NASAs WISE and GALEX missions. These maps have matched resolution (FWHM 7.5 and 15), matched astrometry, and a common procedure for background removal. We demonstrate that they agree well with resolved intensity measurements and integrated photometry from previous surveys. This atlas represents the first part of a program (the z=0 Multi-wavelength Galaxy Synthesis) to create a large, uniform database of resolved measurements of gas and dust in nearby galaxies. The images and associated catalogs are publicly available at the NASA/IPAC Infrared Science Archive. This atlas allows us estimate local and integrated star formation rates (SFRs) and stellar masses (M$_star$) across the local galaxy population in a uniform way. In the appendix, we use the population synthesis fits of Salim et al. (2016, 2018) to calibrate integrated M$_star$ and SFR estimators based on GALEX and WISE. Because they leverage an SDSS-base training set of >100,000 galaxies, these calibrations have high precision and allow us to rigorously compare local galaxies to Sloan Digital Sky Survey results. We provide these SFR and M$_star$ estimates for all galaxies in our sample and show that our results yield a main sequence of star forming galaxies comparable to previous work. We also show the distribution of intensities from resolved galaxies in NUV-to-WISE1 vs. WISE1-to-WISE3 space, which captures much of the key physics accessed by these bands.



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