A Survey for Hα Emission from Late L Dwarfs and T Dwarfs

  title={A Survey for H$\alpha$ Emission from Late L Dwarfs and T Dwarfs},
  author={J. S. Pineda and G. Hallinan and J. Kirkpatrick and G. Cotter and M. Kao and K. Mooley},
  journal={The Astrophysical Journal},
Recently, studies of brown dwarfs have demonstrated that they possess strong magnetic fields and have the potential to produce radio and optical auroral emissions powered by magnetospheric currents. This emission provides the only window on magnetic fields in the coolest brown dwarfs and identifying additional benchmark objects is key to constraining dynamo theory in this regime. To this end, we conducted a new red optical (6300–9700 A) survey with the Keck telescopes looking for Hα emission… Expand
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