LAMOST 2005427-29

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Chen, et al. 2003 -0.075-0.076-0.0990.028FG

Age-Metallicity-RelationAMR for 118 OCsCorrected for radial gradient FG

(20053):

Number of clusters: 1632with Distances: 771 (47.24%) with Reddening: 753 (46.14%) with Ages: 629 (38.54%) with Dist,Redd. and Ages: 615 (37.68%) with Proper motions: 609 (37.32%) with Radial velocities: 234 (14.34%) with P.Motions + RVs: 219 (13.42%) with Dist,Ages,PM and RVs 217 (13.29%) with Abundances: 133 ( 8.15%)

a.018090270 () b.15

2 a. ()80% Rgc>8.5kpc (x,y) (7kpc20)

b. (

LAMOST: Vlim=16.5 (SNR=100, =1H) for F/G stars, ~d=4 kpc for OCs, ~d>10 kpc R=6000~15000 for Vr~5 km/s for [M/H]~0.1dex

HR

Distances reachablefor differenttypes of stars

(Av=0)Hu&Zhao 2003:Dsun~10kpc

SpMVmMdkpcDwarfA00.615.915.1A51.914.68.3F02.713.85.8F53.513.04.0G04.412.12.6G55.111.41.9GiantG50.915.613.2K00.715.814.4K5-0.216.721.9

Model star count /d2 Gilmore & Zeillik 2000

Vb = 0b = 5b = 10b = 30b = 90All-sky 15127312169663901295231630552884214275022211141769506441444613303572239181479113490869022345554286

LAMOST: < 20deg2, ~ 400-600/deg2 -20

LAMOST: LOCSS-- LAMOST Open Clusters Spectroscopic Survey (LAMOST): 40d z< 60d > -20d 800 (> 4-5d) (< 0.2d) 684 0.50.5d~1d1d2d2d(R~16)

680(> -20d )

680(> -20d )

N~3000, F=1d1d ~1

(204) 1d1d3000 31000() 100150

LAMOST1 (400,800,1000)

600105106 Vr () # &() # HR(2MASS)

# () # () # AMR

~ From total of ~680 OCsN~350N~300N~70

LAMOST :

(HR)

Name Alpha(J2000.0)Delta L(J2000.0)B Dsun Dgc Z Age Note h m s d ' " d d pc kpc pc Gyr Berkeley 17 05 20 36 +30 36 00 175.6462 -03.6479 2700 11.19 -172 12.023 oldest King 2 00 51 00 +58 11 00 122.8741 -04.6884 5750 12.58 -470 6.026 no M&Vr Berkeley 20 05 32 37 +00 11 18 203.4833 -17.3727 8400 16.36 -2508 6.026 NGC 6791 19 20 53 +37 46 18 69.9585 +10.9037 5853 8.55 1107 4.395 NGC 2682 08 51 18 +11 48 00 215.6961 +31.8964 908 9.15 480 2.564 NGC 7789 23 57 24 +56 42 30 115.5320 -05.3850 2337 9.73 -219 1.718 NGC 2420 07 38 23 +21 34 24 198.1072 +19.6341 3085 11.35 1037 1.117 Berkeley 29 06 53 18 +16 55 00 197.9835 +08.0248 14871 23.05 2076 1.059 most distno VrBochum 1 06 25 25 +19 46 00 192.4312 +03.4008 2803 11.25 166 0.005 no M&Vr Bochum 2 06 48 54 +00 23 00 212.3015 -00.3897 2661 10.84 -18 0.005 no M NGC 1893 05 22 44 +33 24 42 173.5850 -01.6804 6000 14.48 -176 0.003 no M NGC 2244 06 31 55 +04 56 30 206.3059 -02.0719 1445 9.82 -52 0.008 no M NGC 2264 06 40 58 +09 53 42 202.9358 +02.1959 667 9.12 26 0.009 NGC 6823 19 43 09 +23 18 00 59.4019 -00.1441 1893 7.71 -5 0.007 no M Dolidze 25 06 45 06 +00 18 00 211.9423 -01.2732 6304 14.24 -140 0.007 no M King 6 03 28 06 +56 27 00 143.3607 -00.0765 871 9.21 -1 0.251 noVr NGC 1245 03 14 42 +47 14 12 146.6474 -08.9309 2876 10.99 -446 0.506 no Vr NGC 2099 05 52 18 +32 33 12 177.6354 +03.0915 1383 9.88 75 0.347 NGC 2281 06 48 17 +41 04 42 174.9014 +16.8813 558 9.03 162 0.358 noVr . .. .. Example