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Testing the Disk-Locking Paradigm: An Association Between U-V Excess and Rotation in NGC 2264

Cassandra Fallscheer·William Herbst
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Abstract

We present some results from a UVI photometric study of a field in the young open cluster NGC 2264 aimed, in part, at testing whether accretion in pre-main sequence stars is linked to rotation. We confirm that U-V excess is well correlated with H-alpha equivalent width for the stars in our sample. We show that for the more massive stars in the cluster sample (roughly 0.4-1.2 M_sun) there is also a significant association between U-V excess and rotation, in the sense that slow rotators are more likely to show excess U-band emission and variability. This constitutes significant new evidence in support of the disk-locking paradigm.

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Cassandra Fallscheer, William Herbst. 2006-07-10. Testing the Disk-Locking Paradigm: An Association Between U-V Excess and Rotation in NGC 2264. https://doi.org/10.1086/507525

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