Joe Filippazzo edited untitled.tex  almost 10 years ago

Commit id: d8896ea2ed3c22f9a77bfb20bfd9e337bb490052

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Unable to sustain nuclear fusion in their cores due to insufficient mass, all brown dwarfs are about the radius of Jupiter, emit primarily in the infrared, and are degenerate across effective temperature, mass, and age. These observational challenges make stellar direct measurement methods such as interferometry and asteroseismology unfeasible and dynamical mass measurements very difficult for a large number of objects. large, diverse sample.  However, spectral energy distributions (SED) with optical through mid-infrared data allow detailed spectroscopic study of these objects over a broad wavelength baseline. With the addition of parallaxes, precise bolometric luminosities ($L_{bol}$) become a robust direct measurement by which we can investigate the effects of fundamental parameters on the global characteristics of brown dwarfs. We construct 175 near-complete SEDs for the entire sequence of late-M, L and T dwarfs with optical and near-infrared (NIR) spectra from the BDNYC Data Archive combined with mid-infrared data from the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010) and the Spitzer Space Telscope (Fazio et al. 2004; Houck et al. 2004). Objects with optical signatures of low surface gravity ($\beta$ or $\gamma$; Kirkpatrick et al. 2005, Cruz et al. 2009) or membership in nearby young (10-150 Myr) moving groups (NYMGs; Faherty et al. in prep) are identified as 24 percent of the sample to investigate the effects of temperature, gravity, and dust/clouds on spectral morphology. We calculate $L_{bol}$ for our sample by integration of the SEDs, flux calibrated using parallax measurements from the Brown Dwarf Kinematics Project (Faherty et al. 2012) and the literature (Dupuy et al. 2013, Tinney et al. 2003, Vrba et al. 2004) or published kinematic distances (Cruz et al. 2003, 2007; Faherty et al. 2009; Schmidt et al. 2006, 2010; Reid et al. 2006; Delorme et al. 2012; Naud et al. 2014).