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Metal-Depleted Brown Dwarfs

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Handbook of Exoplanets

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Abstract

This chapter reviews our current knowledge of metal-poor ultracool dwarfs with spectral types later than M7. The current census of M, L, and T subdwarfs is explored. The main color trends of subdwarfs from the optical to the mid-infrared are described and their spectral features presented, which led to a preliminary and tentative spectral classification subject to important changes in the future when more of these metal-poor objects are discovered. Their multiplicity and the determination of their physical parameters (effective temperature, gravity, metallicity, and mass) are discussed. Finally, some suggestions and future guidelines are proposed to foster our knowledge on the oldest and coolest members of our Galaxy.

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Acknowledgements

NL is supported by programme AYA2015-69350-C3-2-P from Spanish Ministry of Economy and Competitiveness (MINECO). NL thanks ZengHua Zhang for his input on the review.

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Authors and Affiliations

  1. Instituto de Astrofísica de Canarias, La Laguna, Spain

    Nicolas Lodieu

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  1. Nicolas Lodieu
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Correspondence to Nicolas Lodieu .

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Editors and Affiliations

  1. Instituto de Astrofísica de Canarias , La Laguna, Spain

    Hans J. Deeg

  2. Instituto de Astrofísica de Canarias, La Laguna, Spain

    Juan Antonio Belmonte

Section Editor information

  1. Centro de Astrobiología, Madrid, Spain

    María Rosa Zapatero-Osorio

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Lodieu, N. (2018). Metal-Depleted Brown Dwarfs. In: Deeg, H., Belmonte, J. (eds) Handbook of Exoplanets . Springer, Cham. https://doi.org/10.1007/978-3-319-30648-3_173-1

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  • DOI: https://doi.org/10.1007/978-3-319-30648-3_173-1

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  • Print ISBN: 978-3-319-30648-3

  • Online ISBN: 978-3-319-30648-3

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