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Status of LAMOST. ZHAO Yongheng National Astronomical Observatories of China. Structure of LAMOST. MA mirror. Fiber Positioning. Fibers. MB mirror. Spectrographs CCDs. Ma: reflecting corrector (24 sub-mirrors) ~ 4.9m Mb: spherical mirror (37 sub-mirrors) ~ 6.1m.
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Status of LAMOST ZHAO Yongheng National Astronomical Observatories of China
Structure of LAMOST MA mirror Fiber Positioning Fibers MB mirror Spectrographs CCDs
Ma: reflecting corrector (24 sub-mirrors) ~ 4.9m • Mb: spherical mirror (37 sub-mirrors) ~ 6.1m
Basic parameters of LAMOST • 4.9m/6.1m Schmidt telescope • The declination of observable sky area ranges from -10 to +90. • 20 square degree of the FOV • 4000 fibers • Spectrum resolution: VPH (Volume Phase Holographic) Grating R=1000, 2000, 5000, 10000
Schedules of LAMOST Project • ReviewedApproved • Proposal Nov. 1996 Apr. 1997 • Feasibility Study Jul. 1997 Aug. 1997 • Preliminary Design Apr.-May 1999 Jun. 1999 • Detailed Design Sep. 2001 • Construction 2001-2008 • First Light 2008
Technical Challenges Active optics Both thin mirror and segmented mirror active optics in MA segmented mirror active optics in MB Fiber positioning 4000 fibers at LAMOST SDSS: 640 fibers 2dF: 400 fibers
LAMOST small system • June 2007 • 6Ma and9 Mb submirror ~ 2m LAMOST • Small focus plane + 250 fibers • 1 spectrograph
Results of Close Loop Active Optics 第九号星闭环跟踪结果(2007.6.8 180组)
LAMOST- Positioning for 4000 fibers Focal Plate for holding 4000 fibers Prototype For 19 fibers In USTC Double arm scheme
LAMOST-LRS Optical System Blue (370~590nm) R5000/10000 R1000/2000 Red (570~900nm) R5000/10000 R1000/2000
Image quality (R=1000) blue red
南京 红区 蓝区 兴隆
First light of the small system • On May 20 2007 The LAMOST small system (about 2m in diameter and have 250 firbers) got its first spectrum!
Sky Skylight in day 5月25日15时
6月5日18时 Skylight spectra
Field No. 9 • June 22, 02h • 203 targets • 3600 • 123 Spectrum
Component & Total Efficiency 1.00 0.80 telescope Efficieny fiber 0.60 Spectrograph 0.40 CCD 0.20 total 0.00 370 450 550 650 750 850 Wavelength(A)
Efficincy • R band • Observe data ( Sky):12.0% • Theoretical value: 16.5% 中值为1
Oct. 8, 2008 Mean=1.14″, Maintenance Mean=1.00″ 80%=1.21″, 80% Maintenance=1.14″
Test spectra(8月25日 3号光谱仪) Blue Red