New Distance Measurements to the $α$ Persei and Pleiades Clusters

Mark A. O'Dell; Martin A. Hendry; Andrew Collier Cameron

doi:10.1093/mnras/268.1.181

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arXiv · astro-ph/9310033

New Distance Measurements to the $α$ Persei and Pleiades Clusters

Mark A. O'Dell·Martin A. Hendry·Andrew Collier Cameron

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Abstract

We apply the new distance measuring technique of Hendry, O'Dell and Collier- Cameron, 1993, to the Pleiades and $α$ Persei clusters. The method relies on knowledge of the periods, rotation velocities and angular diameters of a sample of late-type stars within each cluster. The angular diameters were found by recalibrating the Barnes-Evans surface brightness relation. Applying our new distance method we derive a Pleiades distance in very good agreement with previous ZAMS fitting determinations, whereas our $α$ Persei distance appears substantially greater. In response to this greater distance, we apply a recent semi-empirical main-seqeunce fitting technique to $α$ Persei and confirm the findings of our new distance indicator. (Figures / preprint available on request)

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Mark A. O'Dell, Martin A. Hendry, Andrew Collier Cameron. 1993-10-14. New Distance Measurements to the $α$ Persei and Pleiades Clusters. https://doi.org/10.1093/mnras%2F268.1.181

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