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The Monitor project: Rotation of low-mass stars in the open cluster NGC 2516

Jonathan Irwin·Simon Hodgkin·Suzanne Aigrain·Leslie Hebb·Jerome Bouvier·Cathie Clarke·Estelle Moraux·D. M. Bramich
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Abstract

We report on the results of an i-band time-series photometric survey of NGC 2516 using the CTIO 4m Blanco telescope and 8k Mosaic-II detector, achieving better than 1% photometric precision per data point over 15<~i<~19. Candidate cluster members were selected from a V vs V-I colour magnitude diagram over 16 0.25 days, and the slowest rotators for M<~0.5 M_solar bounded by a line of P \propto M^3, with those for M>~0.5 M_solar following a flatter relation closer to P ~ constant. Models of the rotational evolution were investigated, finding that the evolution of the fastest rotators was well-reproduced by a conventional solid body model with a mass-dependent saturation velocity, whereas core-envelope decoupling was needed to reproduce the evolution of the slowest rotators. None of our models were able to simultaneously reproduce the behaviour of both populations.

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Jonathan Irwin, Simon Hodgkin, Suzanne Aigrain, Leslie Hebb, Jerome Bouvier, Cathie Clarke, Estelle Moraux, D. M. Bramich. 2007-02-20. The Monitor project: Rotation of low-mass stars in the open cluster NGC 2516. https://doi.org/10.1111/j.1365-2966.2007.11640.x

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