Eight new quasars discovered by the Guoshoujing Telescope (LAMOST) in one extragalactic field
Xue-Bing Wu1, Zhen-Dong Jia1, Zhao-Yu Chen1, Wen-Wen Zuo1, Yong-Heng Zhao2, A-li Luo2, Zhong-Rui Bai2, Jian-Jun Chen2, Hao-Tong Zhang2, Hong-Liang Yan2, Juan-Juan Ren2, Shi-Wei Sun2, Hong Wu2, Yong Zhang3, Ye-Ping Li3, Qi-Shuai Lu3, You Wang3, Ji-Jun Ni3, Hai Wang3, Xu Kong4 and Shi-Yin Shen5 1 Department of Astronomy, Peking University, Beijing 100871, China;2 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 3 National Institute of Astronomical Optics & Technology, Chinese Academy of Sciences, Nanjing 210042, China 4 Center for Astrophysics, University of Science & Technology of China, Hefei 230026, China 5 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China
We report the discovery of eight new quasars in one extragalactic field (a five-degree field centered at RA=08h58m08.2s, Dec=01?32'29.7'') with the Guoshoujing Telescope (LAMOST) commissioning observations made on 2009 December 18.These quasars, with i magnitudes from 16.44 to 19.34 and redshifts from 0.898 to 2.773, were not identified in the SDSS spectroscopic survey, though six of them with redshifts less than 2.5 were selected as quasar targets in SDSS.Except for one source without near-IR Y-band data, seven of these eight new quasars satisfy a newly proposed quasar selection criterion involving both near-IR and optical colors.Two of them were found in the ‘redshift desert' for quasars (z from 2.2 to 3), indicating that the new criterion is efficient for uncovering missing quasars with similar optical colors to stars.Although LAMOST encountered some problems during the commissioning observations, we were still able to identify 38 other known SDSS quasars in this field, with i magnitudes from 16.24 to 19.10 and redshifts from 0.297 to 4.512.Our identifications imply that a substantial fraction of quasars may be missing in previous quasar surveys.The implication of our results to the future LAMOST quasar survey is discussed.
【Fund】： supported by the National Natural Science Foundation of China (Grant No.10525313);; the National Key Basic Research Science Foundation of China (2007CB815405);; The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST now called the Guoshoujing Telescope) is a National Major Scientific Project built by the Chinese Academy of Sciences
【CateGory Index】： P158
【CateGory Index】： P158