NGC 6204 and Hogg 22: The odd couple

被引:6
作者
Forbes, D [1 ]
Short, S [1 ]
机构
[1] MEM UNIV NEWFOUNDLAND,DEPT PHYS,SIR WILFRED GRENFELL COLL,CORNER BROOK,NF A2H 6P9,CANADA
关键词
D O I
10.1086/117900
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
New photoelectric UBV photometry has been used to study the overlapping, but distinct, southern open clusters NGC 6204 and Hogg 22. The 36 members identified in NGC 6204 are found to have a mean reddening E(B-V)=0.51+/-0.07 (s.d,), distance modulus (V-0-M(V))=10.35+/-0.09 (s.e,), and age (125+/-25) Myr. A possible Cepheid-like evolved cluster member is shown to be unlikely to belong to the cluster. The younger, more distant cluster Hogg 22 contains 22 identified members and has a mean reddening E(B-V)=0.68+/-0.03 (s.d.), distance modulus (V-0-M(V))=11.75+/-0.14 (s.e.), and age (5+/-2) Myr. Two O-type stars, potential calibrators of the M(V), spectral type relation, are found to be probable cluster members. (C) 1996 American Astronomical Society.
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页码:1609 / 1614
页数:6
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