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Title: DA WHITE DWARFS OBSERVED IN THE LAMOST PILOT SURVEY

Abstract

A total of {approx}640, 000 objects from the LAMOST pilot survey have been publicly released. In this work, we present a catalog of DA white dwarfs (DAWDs) from the entire pilot survey. We outline a new algorithm for the selection of white dwarfs (WDs) by fitting Sersic profiles to the Balmer H{beta}, H{gamma}, and H{delta} lines of the spectra, and calculating the equivalent width of the Ca II K line. Two thousand nine hundred sixty-four candidates are selected by constraining the fitting parameters and the equivalent width of the Ca II K line. All the spectra of candidates are visually inspected. We identify 230 DAWDs (59 of which are already included in the Villanova and SDSS WD catalogs), 20 of which are DAWDs with non-degenerate companions. In addition, 128 candidates are classified as DAWDs/subdwarfs, which means the classifications are ambiguous. The result is consistent with the expected DAWD number estimated based on the LEGUE target selection algorithm.

Authors:
; ; ; ; ; ; ; ; ; ; ; ;  [1];  [2]; ;  [3];  [4]
  1. Key Lab for Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
  2. Department of Astrophysics, Division of Physical Sciences, American Museum of Natural History, Central Park West at 79th Street, New York, NY (United States)
  3. Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States)
  4. University of Science and Technology of China, Hefei 230026 (China)
Publication Date:
OSTI Identifier:
22122890
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 146; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALGORITHMS; CLASSIFICATION; SPECTRA; WHITE DWARF STARS

Citation Formats

Zhang Yueyang, Deng Licai, Liu Chao, Carrell, Kenneth, Yang Fan, Gao Shuang, Xu Yan, Li Jing, Zhang Haotong, Zhao Yongheng, Luo Ali, Bai Zhongrui, Yuan Hailong, Lepine, Sebastien, Newberg, Heidi Jo, Carlin, Jeffrey L., and Jin Ge. DA WHITE DWARFS OBSERVED IN THE LAMOST PILOT SURVEY. United States: N. p., 2013. Web. doi:10.1088/0004-6256/146/2/34.
Zhang Yueyang, Deng Licai, Liu Chao, Carrell, Kenneth, Yang Fan, Gao Shuang, Xu Yan, Li Jing, Zhang Haotong, Zhao Yongheng, Luo Ali, Bai Zhongrui, Yuan Hailong, Lepine, Sebastien, Newberg, Heidi Jo, Carlin, Jeffrey L., & Jin Ge. DA WHITE DWARFS OBSERVED IN THE LAMOST PILOT SURVEY. United States. doi:10.1088/0004-6256/146/2/34.
Zhang Yueyang, Deng Licai, Liu Chao, Carrell, Kenneth, Yang Fan, Gao Shuang, Xu Yan, Li Jing, Zhang Haotong, Zhao Yongheng, Luo Ali, Bai Zhongrui, Yuan Hailong, Lepine, Sebastien, Newberg, Heidi Jo, Carlin, Jeffrey L., and Jin Ge. 2013. "DA WHITE DWARFS OBSERVED IN THE LAMOST PILOT SURVEY". United States. doi:10.1088/0004-6256/146/2/34.
@article{osti_22122890,
title = {DA WHITE DWARFS OBSERVED IN THE LAMOST PILOT SURVEY},
author = {Zhang Yueyang and Deng Licai and Liu Chao and Carrell, Kenneth and Yang Fan and Gao Shuang and Xu Yan and Li Jing and Zhang Haotong and Zhao Yongheng and Luo Ali and Bai Zhongrui and Yuan Hailong and Lepine, Sebastien and Newberg, Heidi Jo and Carlin, Jeffrey L. and Jin Ge},
abstractNote = {A total of {approx}640, 000 objects from the LAMOST pilot survey have been publicly released. In this work, we present a catalog of DA white dwarfs (DAWDs) from the entire pilot survey. We outline a new algorithm for the selection of white dwarfs (WDs) by fitting Sersic profiles to the Balmer H{beta}, H{gamma}, and H{delta} lines of the spectra, and calculating the equivalent width of the Ca II K line. Two thousand nine hundred sixty-four candidates are selected by constraining the fitting parameters and the equivalent width of the Ca II K line. All the spectra of candidates are visually inspected. We identify 230 DAWDs (59 of which are already included in the Villanova and SDSS WD catalogs), 20 of which are DAWDs with non-degenerate companions. In addition, 128 candidates are classified as DAWDs/subdwarfs, which means the classifications are ambiguous. The result is consistent with the expected DAWD number estimated based on the LEGUE target selection algorithm.},
doi = {10.1088/0004-6256/146/2/34},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 2,
volume = 146,
place = {United States},
year = 2013,
month = 8
}
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