大型天文望远镜焦面系统的热力学分析

PerformanceandsensitivityofLowResolutionSpectrographsforLAMOSTZhuYongtian,HouYonghui,HuZhongwenWangLei,WangJianingSanDiego,27June,2010OutlineBrief

introduction--LAMOST--LRSsTestresults--Imagequality

--Throughout

--WavelengthcoverageandresolutionSomeresultsinearlycommissioningobservationLAMOST

SpecificationofLAMOSTEffectiveaperture:D=4mFocalratio:F#=5fieldofview:5degrees

NumberofFibers:4000FRD:f/5→f/4Fibercorediameter:320miconsor3.3″SpecificationofLowResolutionSpectrographThereare16LRSspectrographs250fibersforeachspectrographWavelengthcoverage370nm~900nmResolutionexpected1000~10000TheopticallayoutoftheLAMOST-LRSR1000/2000R5000/10000R5000/10000R1000/2000Blueband(370~590nm)Redband(570~900nm)YongtianZhu,ZhongwenHu,QingfengZhang,etal.Proc.SPIE6269(2006)SpectrographParameters16lowresolutionspectrographs(LRSs)forLAMOST250fibers(3.3arcsecs)/EachspectrographThefibersareseparatedby578μmcentertocenteralongthe144mmheight

arcslitF/4SchmidtcollimatorAdichroicbeam-splitter4VPHgratings/LRS(low,andmediumdispersionrespectively)2articulatingredandblueF/1.3SchmidtcamerasfieldlensCorrectormirrors4096×4136EEVCCD12μmsquarepixelsizeInlaboratoryinXinglongStationVPHGratingsetsofLAMOST-LRSVPHGVPHgratingswavefrontqualityResolutionpowersLow-resolutionmodeMedium-resolutionmode3700–9000ÅR~1000/20005100–5500Å

8300–8900ÅR~5000/1000032CCDDetectorsE2V/EnglandChineseCompanyImagequalityofbluebandforlowresolutionconfiguration

R=1000Imagequalityofredbandforlowresolutionconfiguration(R=1000)Imagequalityformediumresolutionconfiguration(R=5000)ImagequalityImagequality(with1.6″slit)twodimensionalspectraofarclamp(with1.6″slit)ThroughputThroughputofLAMOST-LRSwithoutconsideringtheCCDquantumefficiencyandfibertransmissionlossWavelengthcoverageandresolutionCCDcancoverabout348nm(redband),234nm(blueband)Thewavelengthrange:365-599nm(blueband)565-913nm(redband)Theresolutionatcentralwavelength:1100(at740nm),1040(at480nm)The1DspectrumofarclampThetwilightskyspectraobtainedbyLAMOSTBluebandRedbandSomeobservationresultsduringtheearlycommissioningphase(inthewinter2009)Averybrighti=16.44quasarinthe‘redshiftdesert’discoveredbyLAMOST(Xue-BingWu1,ZhaoyuChen1,ZhendongJiaetal.)(2010)EightnewquasarsdiscoveredbyLAMOSTinoneextragalaticfield

(Xue-BingWu,ZhendongJia,ZhaoyuChenetal.)(2010)LAMOSTDiscoversQuasarsBehindtheAndromeda

Galaxy(Zhi-YingHuo,Xiao-WeiLiu,Hai-BoYuanetal.)(2010)DetectionofNewCandidatesofMetal-poorStarswithLAMOSTCommissioningData

(H.-N.Li,G.Zhao,N.Christlieb)(2010)LAMOSTDiscoversNewPlanetaryNebulaeintheOutskirtsoftheAndromedaGalaxy

(Hai-BoYuan,Xiao-WeiLiu,Zhi-YingHuo)(2010)……Averybrighti=16.44quasarinthe‘redshiftdesert’discoveredbyLAMOST(z=2.427)Leftpanel:TheLAMOSTspectrumofSDSSJ085543.40-001517.7.Rightpanel:ThespectrumofSDSSJ085543.40-001517.7takenbytheNAOC/Xinglong2.16mtelescope.ThescaledSDSScompositequasarspectrum(inredcolor)isshownforcomparisonXue-BingWu,ZhaoyuChen,ZhendongJiaetal.2010acceptedbyRAAEightnewquasars8newquasars(2quasarsintheredshiftdesert)imagnitudes:16.24to19.10z(redshift)0.898to2.773Xue-BingWu,ZhendongJia,ZhaoyuChenetal.2010acceptedbyRAADetectionofNewCandid