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arXiv · 1707.03635

Binary Star Orbits. V. The Nearby White Dwarf - Red Dwarf pair 40 Eri BC

Brian D. Mason·William I. Hartkopf·Korie N. Miles
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Abstract

A new relative orbit solution with new dynamical masses is determined for the nearby white dwarf - red dwarf pair 40 Eri BC. The period is 230.09+/-0.68y. It is predicted to close slowly over the next half-century getting as close as 1.32" in early 2066. We determine masses of 0.575+/-0.018 $m_\odot$ for the white dwarf and 0.2041+/-0.0064 $m_\odot$ for the red dwarf companion. The inconsistency of the masses determined by gravitational redshift and dynamical techniques, due to a premature orbit calculation, no longer exists.

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Brian D. Mason, William I. Hartkopf, Korie N. Miles. 2017-07-19. Binary Star Orbits. V. The Nearby White Dwarf - Red Dwarf pair 40 Eri BC. https://doi.org/10.3847/1538-3881%2Faa803e

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