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arXiv · 2309.11425

Galaxy Zoo DESI: Detailed Morphology Measurements for 8.7M Galaxies in the DESI Legacy Imaging Surveys

Mike Walmsley·Tobias Géron·Sandor Kruk·Anna M. M. Scaife·Chris Lintott·Karen L. Masters·James M. Dawson·Hugh Dickinson·Lucy Fortson·Izzy L. Garland·Kameswara Mantha·David O'Ryan·Jürgen Popp·Brooke Simmons·Elisabeth M. Baeten·Christine Macmillan
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Abstract

We present detailed morphology measurements for 8.67 million galaxies in the DESI Legacy Imaging Surveys (DECaLS, MzLS, and BASS, plus DES). These are automated measurements made by deep learning models trained on Galaxy Zoo volunteer votes. Our models typically predict the fraction of volunteers selecting each answer to within 5-10\% for every answer to every GZ question. The models are trained on newly-collected votes for DESI-LS DR8 images as well as historical votes from GZ DECaLS. We also release the newly-collected votes. Extending our morphology measurements outside of the previously-released DECaLS/SDSS intersection increases our sky coverage by a factor of 4 (5,000 to 19,000 deg$^2$) and allows for full overlap with complementary surveys including ALFALFA and MaNGA.

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Mike Walmsley, Tobias Géron, Sandor Kruk, Anna M. M. Scaife, Chris Lintott, Karen L. Masters, James M. Dawson, Hugh Dickinson, Lucy Fortson, Izzy L. Garland, Kameswara Mantha, David O'Ryan, Jürgen Popp, Brooke Simmons, Elisabeth M. Baeten, Christine Macmillan. 2023-09-20. Galaxy Zoo DESI: Detailed Morphology Measurements for 8.7M Galaxies in the DESI Legacy Imaging Surveys. https://arxiv.org/abs/2309.11425

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