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arXiv · 2112.04010

A New Classification Model for the ZTF Catalog of Periodic Variable Stars

Siu-Hei Cheung·V. Ashley Villar·Ho-Sang Chan·Shirley Ho
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Abstract

Using the second data release from the Zwicky Transient Facility (ZTF, Bellm et al. 2019), Chen et al. (2020) created a ZTF Catalog of Periodic Variable Stars (ZTF CPVS) of 781, 602 periodic variables stars (PVSs) with 11 class labels. Here, we provide a new classification model of PVSs in the ZTF CPVS using a convolutional variational autoencoder and hierarchical random forest. We cross-match the sky-coordinate of PVSs in the ZTF CPVS with those presented in the SIMBAD catalog. We identify non-stellar objects that are not previously classified, including extragalactic objects such as Quasi-Stellar Objects, Active Galactic Nuclei, supernovae and planetary nebulae. We then create a new labelled training set with 13 classes in two levels. We obtain a reasonable level of completeness (> 90 %) for certain classes of PVSs, although we have poorer completeness in other classes (~ 40 % in some cases). Our new labels for the ZTF CPVS are available via Zenodo Cheung et al. (2021).

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Siu-Hei Cheung, V. Ashley Villar, Ho-Sang Chan, Shirley Ho. 2021-12-07. A New Classification Model for the ZTF Catalog of Periodic Variable Stars. https://arxiv.org/abs/2112.04010

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