Characterization of Dwarf Novae Using SDSS Colors

Kato Taichi

Maehara Hiroyuki

Uemura Makoto

Publications of the Astronomical Society of Japan

We have developed a method for estimating the orbital periods of dwarf novae from the Sloan Digital Sky Survey (SDSS) colors in quiescence using an artificial neural network. For typical objects below the period gap with sufficient photometric accuracy, we were able to estimate the orbital periods with an accuracy to a 1 σ error of 22 %. The error of estimation is worse for systems with longer orbital periods. We have also developed a neural-network-based method for categorical classification. This method has proven to be efficient in classifying objects into three categories (WZ Sge type, SU UMa type and SS Cyg/Z Cam type) and works for very faint objects to a limit of g=21. Using this method, we have investigated the distribution of the orbital periods of dwarf novae from a modern transient survey (Catalina Real-Time Survey). Using Bayesian analysis developed by Uemura et al. (2010), we have found that the present sample tends to give a flatter distribution toward the shortest period and a shorter estimate of the period minimum, which may have resulted from the uncertainties in the neural network analysis and photometric errors. We also provide estimated orbital periods, estimated classifications and supplementary information on known dwarf novae with quiescent SDSS photometry.

methods: statistical — stars: novae, cataclysmic variables — stars: dwarf novae — stars: evolution — surveys

Astronomy. Space sciences [ 440 ]

eng

Astronomical Society of Japan

Copyright (c) 2012 The Astronomical Society of Japan

This is not the published version. Please cite only the published version. この論文は出版社版でありません。引用の際には出版社版をご確認ご利用ください。

[ISSN] 0004-6264

[NCID] AA1082896X

[DOI] 10.1093/pasj/64.3.63

[DOI] https://doi.org/10.1093/pasj/64.3.63

[arXiv] arXiv:1111.4286