Metal-Depleted Brown Dwarfs

  • Nicolas LodieuEmail author
Reference work entry


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.


Metal-poor dwarfs Low-mass stars and brown dwarfs Techniques: photometry spectroscopy 



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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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Instituto de Astrofísica de CanariasLa LagunaSpain

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