High resolution spectroscopy of Brown Dwarfs in Taurus

نویسنده

  • David Barrado
چکیده

We present high resolution optical spectroscopy of three candidate members of the Taurus-Auriga star forming region. Based on the spectral type, the strength, profile and width of the Hα line, the detected lithium at 6708 Å, the location of these objects in a H-R diagram and the comparison with similar objects belonging to young stellar associations, we determine that they are bona fide members of the SFR, with about ∼3 Myr, have masses at or below the substellar limit and, at least in one case, there is active accretion from a circum(sub)stellar disk. This result suggests that high mass brown dwarfs go through a Classical TTauri phase and form like stars, from colapse and fragmentation of a molecular cloud.

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تاریخ انتشار 2004