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arXiv · 1810.07387

Double-peaked Narrow Emission-line Galaxies in LAMOST Survey

M. X. Wang·A. L. Luo·Y. H. Song·S. Y. Shen·S. Feng·L. L. Wang·Y. F. Wang·Y. -B. Li·B. Du·W. Hou·Y. X. Guo·X. Kong·J. N. Zhang
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Abstract

We outline a full-scale search for galaxies exhibiting double-peaked profiles of promi- nent narrow emission lines, motivated by the prospect of finding objects related to merging galaxies, and even dual active galactic nuclei candidates as by-product, from the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST) Data Re- lease 4. We assemble a large sample of 325 candidates with double-peaked or strong asymmetric narrow emission lines, with 33 objects therein appearing optically resolved dual-cored structures, close companions or signs of recent interaction on the Sloan Dig- ital Sky Survey images. A candidate from LAMOST (J074810.95+281349.2) is also stressed here based on the kinematic and spatial decompositions of the double-peaked narrow emission line target, with analysis from the cross-referenced Mapping Nearby Galaxies at the Apache Point Observatory (MaNGA) survey datacube. MaNGA en- ables us to constrain the origin of double peaks for these sources, and with the IFU data we infer that the most promising origin of double-peaked profiles for LAMOST J074810.95+281349.2 is the `Rotation Dominated + Disturbance' structure.

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M. X. Wang, A. L. Luo, Y. H. Song, S. Y. Shen, S. Feng, L. L. Wang, Y. F. Wang, Y. -B. Li, B. Du, W. Hou, Y. X. Guo, X. Kong, J. N. Zhang. 2018-10-22. Double-peaked Narrow Emission-line Galaxies in LAMOST Survey. https://doi.org/10.1093/mnras%2Fsty2818

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