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arXiv · 2101.09888

The Araucaria Project: Deep near-infrared photometric maps of Local and Sculptor Group galaxies. I. Carina, Fornax, Sculptor

Paulina Karczmarek·Grzegorz Pietrzyński·Wolfgang Gieren·Weronika Narloch·Gergely Hajdu·Gonzalo Rojas García·Mikołaj Kałuszyński·Marek Górski·Ksenia Suchomska·Dariusz Graczyk·Bogumił Pilecki·Piotr Wielgórski·Bartłomiej Zgirski·Mónica Taormina·Mradumay Sadh
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Abstract

Deep near-infrared $J$- and $K$-band photometry of three Local Group dwarf spheroidal galaxies: Fornax, Carina, and Sculptor, is made available for the community. Until now, these data have only been used by the Araucaria Project to determine distances using the tip of the red giant and RR Lyrae stars. Now, we present the entire data collection in a form of a database, consisting of accurate $J$- and $K$-band magnitudes, sky coordinates, ellipticity measurements, and timestamps of observations, complemented by stars' loci in their reference images. Depth of our photometry reaches about 22 mag at 5$\sigma$ level, and is comparable to NIR surveys, like the UKIRT Infrared Deep Sky Survey (UKIDSS) or the VISTA Hemisphere Survey (VHS). Small overlap with VHS and no overlap with UKIDSS makes our database a unique source of quality photometry.

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Paulina Karczmarek, Grzegorz Pietrzyński, Wolfgang Gieren, Weronika Narloch, Gergely Hajdu, Gonzalo Rojas García, Mikołaj Kałuszyński, Marek Górski, Ksenia Suchomska, Dariusz Graczyk, Bogumił Pilecki, Piotr Wielgórski, Bartłomiej Zgirski, Mónica Taormina, Mradumay Sadh. 2021-01-25. The Araucaria Project: Deep near-infrared photometric maps of Local and Sculptor Group galaxies. I. Carina, Fornax, Sculptor. https://doi.org/10.3847/1538-4365%2Fabdf60

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