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A New Method of Wavelength Calibration for LAMOST by Combining Short- and Long-Exposure Spectral Lines

Published online by Cambridge University Press:  02 January 2013

G. H. Ye
Affiliation:
Institute of Statistical Signal Processing, Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230027, P. R. China
J. Zhu
Affiliation:
Institute of Statistical Signal Processing, Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230027, P. R. China
Z. F. Ye*
Affiliation:
Institute of Statistical Signal Processing, Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230027, P. R. China
*
BCorresponding author. Email: yezf@ustc.edu.cn
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Abstract

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In wavelength calibration using arc lines, the normal approach is to use the strongest unsaturated lines, leaving weak lines unused. A new method is proposed in this paper, which not only utilizes the strong spectral lines, but also makes most use of weak spectral lines. In order to validate the effectiveness of the method we propose, experiments are performed on simulated spectra. Firstly, two kinds of spectra are generated: one with a short exposure and another with a long exposure. Secondly, calibration lines are chosen from the short exposure and long exposure spectra separately according to some rules. Thirdly, the initial wavelength calibration is completed by using the selected short-exposure lines. Fourthly, the approximate centroids of the selected long-exposure lines are obtained by utilizing the result of the initial wavelength calibration. These are then adjusted iteratively to obtain the centroids. Finally, the selected lines from the short- and long-exposures are combined to obtain the final wavelength calibration. Compared with traditional calibration methods which only use short exposures and strong lines, the proposed method is shown to be more accurate.

Type
Research Article
Copyright
Copyright © Astronomical Society of Australia 2012

References

Bai, L., Liao, N. F., Li, Z. J. & Yang, W. P., 2004, ChOpL, 2, 174Google Scholar
Balona, L. A., 2010, MNRAS, 409, 1601CrossRefGoogle Scholar
Burles, S., Finkbeiner, D. & Schlegel, D., 2008, available at http://das.sdss.org/software/idlspec2d/v5312/pro/spec2d/Google Scholar
Lo, E. & Fountain, A. W., 2006, SPIE, 6233, 62330LGoogle Scholar
Qin, H. Q., Zhu, J., Zhu, Z. Q., Ye, Z. F. & Luo, A. L., 2010, PASA, 27, 265CrossRefGoogle Scholar
Sanchez, S. F., 2006, AN, 327, 850Google Scholar
Su, D. Q., Cui, Y. Q., Wang, Y. N. & Yao, Z. Y., 1998, SPIE, 3352, 76Google Scholar
Van Geffen, J. H. G. M. & Van Oss, R. F., 2003, ApOpt, 42, 2739Google Scholar
Wang, S., Qin, H. Q. & Ye, Z. F., 2010, EA, 28, 195Google Scholar
Xue, X. L. & Ye, Z. F., 2009, AR&T, 6, 181Google Scholar
Zhu, Y. T., Hu, Z. W., Zhang, Q. F., Wang, L. & Wang, J. N., 2006, SPIE, 6269, 62690MGoogle Scholar