Abstract
The incidence of accidental errors of proper motion data in the solution of the stellar membership to open clusters is analysed. A mixed bivatiate normal model with correlation coefficient is used. The parameters of this mixture are determined by the maximum likelihood method solving a fourteen non linear equation system with constraints on the correlation, the percentage o field stars and the standard deviations. The method is applied to sol ve the membership problem in the open cluster NGC2287 and a comparison with those membership results from proper motions without' the consideration of accidental errors is made.
Keywords
References
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