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arXiv · 1710.11014

The oldest stars of the bulge: new information on the ancient Galaxy

Gabriele Cescutti·Cristina Chiappini·Raphael Hirschi
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Abstract

Recently the search for the oldest stars have started to focus on the Bulge region. The Galactic bulge hosts extremely old stars, with ages compatible with the ages of the oldest halo stars. The data coming from these recent observations present new chemical signatures and therefore provide complementary constraints to those already found in the halo. So, the study of the oldest bulge stars can improve dramatically the constraints on the nature of first stars and how they polluted the pristine ISM of our Galaxy. We present our first results regarding the light elements (CNO) and the neutron capture elements. Our findings in the oldest bulge stars support the scenario where the first stellar generations have been fast rotators.

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Gabriele Cescutti, Cristina Chiappini, Raphael Hirschi. 2017-10-30. The oldest stars of the bulge: new information on the ancient Galaxy. https://doi.org/10.1017/s1743921317008183

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