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arXiv · 1404.7218

A Search for Double-peaked narrow emission line Galaxies and AGNs in the LAMOST DR1

Zhi-Xin Shi·A-Li Luo·Georges Comte·Xiao-Yan Chen·Peng-Wei·Yong-Heng Zhao·Fu-Chao Wu·Yan-Xia Zhang·Shi-Yin Shen·Ming Yang·Hong Wu·Xue-Bing Wu·Hao-Tong Zhang·Ya-Juan Lei·Jian-Nan Zhang·Ting-Gui Wang·Ge Jin·Yong Zhang
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Abstract

LAMOST has released more than two million spectra, which provide the opportunity to search for double-peaked narrow emission line (NEL) galaxies and AGNs. The double-peaked narrow-line profiles can be well modeled by two velocity components, respectively blueshifted and redshifted with respect to the systemic recession velocity. This paper presents 20 double-peaked NEL galaxies and AGNs found from LAMOST DR1 using a search method based on multi-gaussian fit of the narrow emission lines. Among them, 10 have already been published by other authors, either listed as genuine double-peaked NEL objects or as asymmetric NEL objects, the remaining 10 being first discoveries. We discuss some possible origins for double-peaked narrow-line features, as interaction between jet and narrow line regions, interaction with companion galaxies and black hole binaries. Spatially resolved optical imaging and/or follow-up observations in other spectral bands are needed to further discuss the physical mechanisms at work.

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Zhi-Xin Shi, A-Li Luo, Georges Comte, Xiao-Yan Chen, Peng-Wei, Yong-Heng Zhao, Fu-Chao Wu, Yan-Xia Zhang, Shi-Yin Shen, Ming Yang, Hong Wu, Xue-Bing Wu, Hao-Tong Zhang, Ya-Juan Lei, Jian-Nan Zhang, Ting-Gui Wang, Ge Jin, Yong Zhang. 2014-04-29. A Search for Double-peaked narrow emission line Galaxies and AGNs in the LAMOST DR1. https://doi.org/10.1088/1674-4527/14/10/003

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