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Title: A New Classification Model for the ZTF Catalog of Periodic Variable Stars
Abstract Using the second data release from the Zwicky Transient Facility (ZTF), Chen et al. 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 labeled 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.  more » « less
Award ID(s):
2108676 2433718
PAR ID:
10353412
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Research Notes of the AAS
Volume:
5
Issue:
12
ISSN:
2515-5172
Page Range / eLocation ID:
282
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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