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arXiv · 1309.1422

Distances, Luminosities, and Temperatures of the Coldest Known Substellar Objects

Trent J. Dupuy·Adam L. Kraus
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Abstract

The coolest known brown dwarfs are our best analogs to extrasolar gas-giant planets. The prolific detections of such cold substellar objects in the past two years has spurred intensive followup, but the lack of accurate distances is a key gap in our understanding. We present a large sample of precise distances based on homogeneous mid-infrared astrometry that robustly establish absolute fluxes, luminosities, and temperatures. The coolest brown dwarfs have temperatures of 400-450 K and masses ~5-20 times that of Jupiter, showing they bridge the gap between hotter brown dwarfs and gas-giant planets. At these extremes, spectral energy distributions no longer follow a simple correspondence with temperature, suggesting an increasing role of other physical parameters such as surface gravity, vertical mixing, clouds, and metallicity.

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Trent J. Dupuy, Adam L. Kraus. 2013-09-05. Distances, Luminosities, and Temperatures of the Coldest Known Substellar Objects. https://doi.org/10.1126/science.1241917

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