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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
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20億5千万年前の星群の観測から,冷たい星の回転時計

Søren Meibom1, Sydney A Barnes2, Imants Platais3

  • 1Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.

Nature
|December 25, 2014
PubMed
まとめ

星の年齢を決定するのは難しい. この研究は,NGC 6819の冷たい恒星の自転速度を用いて回転年代測定を校正し,多くの恒星の正確な年齢を決定します.

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