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Lithium abundance/surface activity connections in solar-type Pleiads

D. Clarke·E. C. MacDonald·S. Owens
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Abstract

The relation between the lithium abundance, A_Li, and photospheric activity of solar-type Pleiads is investigated for the first time via acquisition and analysis of B and V-band data. Predictions of activity levels of target stars were made according to the A_Li/(B-V) relation and then compared with new CCD photometric measurements. Six sources behaved according to the predictions while one star (HII 676), with low predicted activity, exhibited the largest variability of the study; another star (HII 3197), with high predicted activity, was surprisingly quiet. Two stars displayed non-periodic fadings, this being symptomatic of orbiting disk-like structures with irregular density distributions. Although the observation windows were not ideal for rotational period detection, some periodograms provided possible values; the light-curve obtained for HII 1532 is consistent with that previously recorded.

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D. Clarke, E. C. MacDonald, S. Owens. 2003-12-03. Lithium abundance/surface activity connections in solar-type Pleiads. https://doi.org/10.1051/0004-6361%3A20034620

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