広視野多天體高分散分光探銀河系形成史

1、広視野多天體分光銀河系局部銀河群広視野多天體高分散分光探銀河系形成史本田 敏志（NAOJ）青木和光、Tim Beers、Brian Yanny超広視撮像/分光器切開銀河天文學(xué)観測的宇宙論（NAOJ） （MSU & JINA）（Fermilab） 銀河考古學(xué)n銀河系、作、進(jìn)化？n金屬欠乏星銀河系形成頃現(xiàn)在進(jìn)化情報(bào)保持。n放射性元素年代測定可能。n第一世代星探査重要。第一世代星研究nPopn金屬量古星n元素合成過程反映期待n第二世代星n宇宙最初超新星爆発反映n宇宙初期星形成、化學(xué)進(jìn)化制限與nHE 0107-5140nFe/H=-5.3 V=15.2giant nVLT/UVESChristlieb

2、 et al. 2002nHE 1327-2326nFe/H=-5.6 V=13.5 subgiantn/HDS Frebel et al. 2005、Aoki et al. 2005第一世代星探査n低金屬星観測（104）n高速度星nBond et al. 1970,1980nHKnBeers et al. 1985,1992,1999nHamburg/ESOnChristlieb et al. 2001n中分散分光観測（103）n24m級望遠(yuǎn)鏡n大口徑望遠(yuǎn)鏡高分散分光観測（102）n/HDS、VLT/UVES、Keck/HIRES0.05dex？Ryan et al. 1996Cayrel

3、et al. 2004超金屬欠乏星（Fe/H-2.5）化學(xué)組成MgMg無？観測誤差？Aoki et al. 2006超金屬欠乏星（Fe/H-2.5）化學(xué)組成-5Fe/H-4 ？Ba中性子捕獲元素検出Fe/H以下無EuHonda et al. 2004Aoki et al. 2005観測十分？n今観測太陽近傍一部星。nFe/H-3星非常少n特-5Fe/H-4無n組成空間分布?nhalo、disk組成違？nMetallicity Distribution Function?n大規(guī)模高分散分光観測必要n球狀星団、矮小銀河星含？深眠遺跡発掘調(diào)査必要！観測低中分散n、nHKnHESnSDSSnHippa

4、rcosn今後nSEGUEnSDSS-IInLAMOST(中國)n4m多天體分光望遠(yuǎn)鏡nR=1000-3000、n2007nGAIA（ESA）n2011nRAVEn2011V15V18SDSS-IISEGUE The Sloan Extension for Galactic Understanding and Evolutionn240,000星n測光使大気求n金屬量RV見積n誤差 0.3dex10kmn38009000R1800n13.520.5n20052008期間nFe/H -2.0 20,000nFe/H -3.0 2,000nFe/H -4.0 200 ?nFe/H -5.0 20

5、?nFe/H -6.0 2 ? 8 kpcKVGMSTO/FBHB/BSK IIISEGUE uses stellar probes of increasingabsolute brightness to probeincreasing distances in the disk, thick disk and Milky Way halo.d 1 kpcd 6 kpcd 15 kpcd 50 kpcd 100 kpcOther spectroscopic surveys will not probe as deep,for instance, Blue Horizontal Branch S

6、tars (BHBs) from a survey with V 12 are from a volume within 1.5 kpc of the sun.r = 1.5kpcStreams and outer halo starsInner and outer halo starsthin, thickdisk starsSEGUE Status as of Sept 1, 2006 (end of Year 1 of 3)2271/3500 square degrees of imaging completed (64%), most remaining stripes inlate South (winter observing),146/400 plates completed (36%), more remaining tiles in North (spring observing)./HDS観測nSEGUE発見C-rich星低金屬星高分散得、組成調(diào)。Suns2Fe/H=-2.5C-richs2Fe/H=-3.5seg_2314-0906100KFe/H=-3.3C-richpreli