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AB Doradus C: Age, Spectral Type, Orbit, and Comparison to Evolutionary Models

E. L. Nielsen·L. M. Close·J. C. Guirado·B. A. Biller·R. Lenzen·W. Brandner·M. Hartung·C. Lidman
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Abstract

We expand upon the results of Close et al. 2005 regarding the young, low-mass object AB Dor C and its role as a calibration point for theoretical tracks. We present an improved spectral reduction and a new orbital solution with two additional epochs. Our improved analysis confirms our spectral type of M8 (+/- 1) and mass of 0.090+/-0.003 solar masses for AB Dor C. Comparing the results for AB Dor C with other young, low-mass objects with dynamical masses we find a general trend where current evolutionary models tend to over-predict the temperature (or under-predict the mass) for low mass stars and brown dwarfs. Given our precision, there is a ~99% chance that the mass of AB Dor C is underestimated by the DUSTY tracks in the HR diagram.

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E. L. Nielsen, L. M. Close, J. C. Guirado, B. A. Biller, R. Lenzen, W. Brandner, M. Hartung, C. Lidman. 2005-09-14. AB Doradus C: Age, Spectral Type, Orbit, and Comparison to Evolutionary Models. https://doi.org/10.1002/asna.200510442

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