A WIYN Lithium Survey for Young Stars in the λ Orionis Star-forming Region

  title={A WIYN Lithium Survey for Young Stars in the $\lambda$ Orionis Star-forming Region},
  author={Christopher J. Dolan and Robert D. Mathieu},
  journal={The Astronomical Journal},
  pages={2409 - 2423}
We have found 72 pre–main-sequence (PMS) stars near the center of the λ Orionis star-forming region by spectroscopically testing a magnitude-limited sample for the presence of lithium λ6708 absorption, a diagnostic of youth. All of these stars show large lithium equivalent widths and radial velocities consistent with Orion membership, but only two were discovered previously via Hα or X-ray surveys. Comparison with PMS evolutionary tracks show that the low-mass star formation did not begin prior… 

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