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تسجيل مستخدم جديدThe R1R2 outer ring revealed by young open cluster data
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The distribution of young open clusters in the Galactic plane suggests the existence of the outer ring R1R2 in the Galaxy. The solar position angle theta_b providing the best agreement between the observed and model distribution is theta_b=35 +- 10 degrees. We compared the theta_b values derived from three different catalogues of open cluster and they appear to be consistent within the errors.
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