RCSEDv2: homogenization of multi-wavelength photometric data

Victoria Toptun; Igor Chilingarian; Ivan Katkov; Kirill Grishin; Anastasia Kasparova; Sviatoslav Borisov; Evgenii Rubtsov; Vladimir Goradzhanov; Vladislav Klochkov

arXiv · 2112.04868

RCSEDv2: homogenization of multi-wavelength photometric data

Victoria Toptun·Igor Chilingarian·Ivan Katkov·Kirill Grishin·Anastasia Kasparova·Sviatoslav Borisov·Evgenii Rubtsov·Vladimir Goradzhanov·Vladislav Klochkov

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Abstract

RCSEDv2 (https://rcsed2.voxastro.org/), the second Reference Catalog of Spectral Energy Distributions of galaxies includes the largest homogeneously processed photometric dataset for 4 million galaxies assembled from several wide-field surveys. Here we describe the methodology of the photometric data homogenization. We first correct all photometric measurements for the foreground Galactic extinction, then convert them into the photometric system we adopted as a standard (GALEX + SDSS + UKIDSS + WISE). We computed aperture corrections into several pre-defined apertures by using published galaxy sizes / light profiles and image quality for each of the surveys. We accounted for k-corrections using our own analytic approximations. Such a homogeneous photometric catalog allows us to build fully calibrated SEDs for the galaxies in our sample (defined by the availability of their spectra) and enables direct scientific analysis of this unique extragalactic dataset.

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Victoria Toptun, Igor Chilingarian, Ivan Katkov, Kirill Grishin, Anastasia Kasparova, Sviatoslav Borisov, Evgenii Rubtsov, Vladimir Goradzhanov, Vladislav Klochkov. 2021-12-09. RCSEDv2: homogenization of multi-wavelength photometric data. https://arxiv.org/abs/2112.04868

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