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arXiv · 2106.12787

J-PLUS: Support Vector Machine Applied to STAR-GALAXY-QSOClassification

Cunshi Wang·Yu Bai·C. López-Sanjuan·Haibo Yuan·Song Wang·Jifeng Liu·David Sobral·P. O. Baqui·E. L. Martín·Carlos Andres Galarza·J. Alcaniz·R. E. Angulo·A. J. Cenarro·D. Cristóbal-Hornillos·R. A. Dupke·A. Ederoclite·C. Hernández-Monteagudo·A. Marín-Franch·M. Moles·L. Sodré Jr.·H. Vázquez Ramió·J. Varela
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Abstract

Context. In modern astronomy, machine learning has proved to be efficient and effective to mine the big data from the newesttelescopes. Spectral surveys enable us to characterize millions of objects, while long exposure time observations and wide surveysconstrain their strides from millions to billions. Aims.In this study, we construct a supervised machine learning algorithm, to classify the objects in the Javalambre Photometric LocalUniverse Survey first data release (J-PLUS DR1). Methods.The sample set is featured with 12-waveband photometry, and magnitudes are labeled with spectrum-based catalogs, in-cluding Sloan Digital Sky Survey spectroscopic data, Large Sky Area Multi-Object Fiber Spectroscopic Telescope, and VERONCAT- Veron Catalog of Quasars & AGN. The performance of the classifier is presented with applications of blind test validations basedon RAdial Velocity Extension, Kepler Input Catalog, 2 MASS Redshift Survey, and the UV-bright Quasar Survey. A new algorithmis applied to constrain the extrapolation that could decrease accuracies for many machine learning classifiers. Results.The accuracies of the classifier are 96.5% in blind test and 97.0% in training cross validation. The F1-scores for each classare presented to show the precision of the classifier. We also discuss different methods to constrain the po

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Cunshi Wang, Yu Bai, C. López-Sanjuan, Haibo Yuan, Song Wang, Jifeng Liu, David Sobral, P. O. Baqui, E. L. Martín, Carlos Andres Galarza, J. Alcaniz, R. E. Angulo, A. J. Cenarro, D. Cristóbal-Hornillos, R. A. Dupke, A. Ederoclite, C. Hernández-Monteagudo, A. Marín-Franch, M. Moles, L. Sodré Jr., H. Vázquez Ramió, J. Varela. 2021-12-24. J-PLUS: Support Vector Machine Applied to STAR-GALAXY-QSOClassification. https://doi.org/10.1051/0004-6361%2F202142254

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