LAMOST Extragalactic Surveys (LEGAS) Yipeng Jing Shanghai Astronomical Observatory For the LEGAS working group LAMOST 2010/07/27 2011 LAMOST SDSS III 2010 U 2011 1 r=19.5,S/N=10 i=20.5,S/N=5 EMG SDSS III ELG sampling factor SRS Sceience Requuirements Specification SRS 2011 ELG LAMOST LAMOST LAMOST fellowship RMB Oct 20, 2007 Structure of LAMOST MB mirror Fiber Positioning Fibers MA mirror Spectrographs CCDs Main Parameters Main function spectroscopic sky survey Effective aperture 4 meter Focal length 20 meter Angular FOV5 linear FOV 1.75-meter Image quality 80% energy encircled in 2.0 acrsec Number of optical fiber 4000 Observing sky area -10 +90 24,000 square degrees Spectral resolution nm Survey capability taking spectral resolution 1nm, integration time 1.5 hours, max bj magnitude: 20.5 m at Xinlong Size of fiber 3.30 arcsec 320 m linear History and current planning reviewed approved Proposal Nov Apr Feasibility Study Jul Aug Preliminary Design Apr.-May 1999 Jun Detailed Design Sep Construction First Light, 3000 spectra at once 2008 Oct Commissioning Start surveys 2011/2010 Task: make a proposal Contributions to LEGAS proposal Working Group: Members: Jing Yipeng, Zhou Xu, Chen Xuelei, Wu Hong, Wu Xuebing, Zheng Xianzhong,Shen Shiyin, Wang Junxian, Li Cheng, Fan Xiaohui LAMOST engineering contacts: Zhang Haotong, Zhang Yanxia, Luo Ali, Chen Jianjun. Wang Tinggui, Chu Yaoquan, Kong Xu, Yang Xiaohu, Zheng Zheng, Zhang Pengjie, Yuan Weimin, Gao Yu, Jun Pan, Zhou Hongyan, Shang Zhaohui, Lu Youjun, XiaXiaoyang, Liu Fengshan, Wang Jianling, Liang Yanchun, Zhang Wei, Fan Zuhui, Zhang Xinmin, Li Hong, Wang Yougang, Wu Fengquan..(incomplete) 60 staff members + >120 students and postdocs in China are expected to analyze the LEGAS data Cutting-edge problems for LAMOST (I) The physical properties of dark energy, the neutrino mass, the physical properties of initial density fluctuation in the early Universe etc, which can be addressed with a better determination of large scale structures on scales 100 h1Mpc; The generic predictions of the cold dark matter model, such as dark matter halos and especially subhalos around galaxies, which can be tested with a bigger sample of groups of galaxies combined with future deep imaging surveys (e.g. Pan-Starrs and LSST) ; Cutting-edge problems for LAMOST (II) The physical processes of galaxy formation, such as galaxy interaction, galaxy merging, energy feedback etc, which can be addressed with a denser sampling of structures to a fainter luminosity limit in our local Universe; The growth of supermassive black holes and the co-evolution with their host galaxies, which can be addressed with a better sampling of quasars at z=1-3 and a larger sample of low-z AGNs. Proposed LEGAS Surveys (the most optimistic) Spectroscopic Surveys of galaxies and QSOs in the NGC of 8000 sq degrees (SDSS sky) and in the SGC of about 3500 sq degrees: LAMOST Galaxy Deep Survey; 2.3 million of r3000 square degrees Pilot surveys 140 square degrees sky areas at high Galactic latitude r