Age determination of the open cluster NGC 2287 (M41)

Küçük, İbrahim
Eryurtezer, Dilan
We have estimated the age of the open cluster NGC 2287 (M41) by taking into account the rotation of the member stars. TheUBV photoelectric measurement values were taken from Eggen (1974). Besides the Main-Sequence stars this cluster has seven red giants, all of them above the turn-off point. Having obtained the theoretical Hertzsprung-Russell diagram from observed colour-magnitude diagram, we have discussed two methods, given in the literature, to estimate the age of the cluster under consideration. The first method we have followed is to determine the turn-off point on the cluster Main-Sequence. The other is fitting the position of the red giants with the evolutionary tracks of rotating stars with different masses on the Hertzsprung-Russell diagram. We have estimated the cluster age based on the turn-off point as 3.10×107 yr. From the fitting of the evolutionary tracks of rotating stars to the cluster Hertzsprung-Russell diagram, we infer that the age of the cluster is about 8.00×107 yr.
Astrophysics and Space Science


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Citation Formats
İ. Küçük and D. Eryurtezer, “Age determination of the open cluster NGC 2287 (M41),” Astrophysics and Space Science, pp. 137–143, 1988, Accessed: 00, 2020. [Online]. Available: