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Deep Learning Assessment of galaxy morphology in S-PLUS DataRelease 1

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 نشر من قبل Clecio Bom
 تاريخ النشر 2021
  مجال البحث فيزياء
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The morphological classification of galaxies is a relevant probe for galaxy evolution and unveils its connection with cosmological structure formation. To this scope, it is fundamental to recover galaxy morphologies over large areas of the sky. In this paper, we present a morphological catalogue for galaxies in the Stripe-82 area, observed with S-PLUS, till a magnitude limit of $rle17$, using the state-of-the-art of Convolutional Neural Networks (CNNs) for computer vision. This analysis will then be extended to the whole S-PLUS survey data, covering $simeq 9300$ $deg^{2}$ of the celestial sphere in twelve optical bands. We find that the networks performance increases with 5 broad bands and additional 3 narrow bands compared to our baseline with 3 bands. However, it does lose performance when using the full $12$ band image information. Nevertheless, the best result is achieved with 3 bands, when using pre-trained network weights in an ImageNet dataset. These results enhance the importance of previous knowledge in the neural network weights based on training in non related extensive datasets. Thus, we release a model pre-trained in several bands that could be adapted to other surveys. We develop a catalogue of 3274 galaxies in Stripe-82 that are not presented in Galaxy Zoo 1 (GZ1). We also add classification to 4686 galaxies considered ambiguous in GZ1 dataset. Finally, we present a prospect of a novel way to take advantage of $12$ bands information for morphological classification using multiband morphometric features. The morphological catalogues are publicly available.



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