English

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

Instrumentation and Methods for Astrophysics 2021-12-09 v1 Solar and Stellar Astrophysics

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).

Keywords

Cite

@article{arxiv.2112.04010,
  title  = {A New Classification Model for the ZTF Catalog of Periodic Variable Stars},
  author = {Siu-Hei Cheung and V. Ashley Villar and Ho-Sang Chan and Shirley Ho},
  journal= {arXiv preprint arXiv:2112.04010},
  year   = {2021}
}

Comments

4 pages, 1 figure