The Mass and Radius of the Unseen M Dwarf Companion in the Single‐Lined Eclipsing Binary HAT‐TR‐205‐013

  • Beatty T
  • Fernandez J
  • Latham D
  • et al.
59Citations
Citations of this article
17Readers
Mendeley users who have this article in their library.

Abstract

We derive masses and radii for both components in the single-lined eclipsing binary HAT-TR-205-013, which consists of an F7 V primary and a late M dwarf secondary. The system's period is short, P = 2.230736 ± 0.000010 days, with an orbit indistinguishable from circular, e = 0.012 ± 0.021. We demonstrate generally that the surface gravity of the secondary star in a single-lined binary undergoing total eclipses can be derived from characteristics of the light curve and spectroscopic orbit. This constrains the secondary to a unique line in the mass-radius diagram, with M/R 2 = constant. For HAT-TR-205-013, we assume the orbit has been tidally circularized and that the primary's rotation has been synchronized and aligned with the orbital axis. Our observed line broadening, V rot sin i rot = 28.9 ± 1.0 km s -1 , gives a primary radius of R A = 1.28 ± 0.04 R ⊙ . Our light-curve analysis leads to the radius of the secondary, R B = 0.167 ± 0.006 R ⊙ , and the semimajor axis of the orbit, a = 7.54 ± 0.30 M ⊙ = 0.0351 ± 0.0014 AU. Our single-lined spectroscopic orbit and the semimajor axis then yield the individual masses M B = 0.124 ± 0.010 M ⊙ and M A = 1.04 ± 0.13 M ⊙ . Our result for HAT-TR-205-013 B lies above the theoretical mass-radius models from the Lyon group, consistent with results from double-lined eclipsing binaries. The method we describe offers the opportunity to study the very low end of the stellar mass-radius relation. © 2007, The American Astronomical Society. All rights reserved.

Cite

CITATION STYLE

APA

Beatty, T. G., Fernandez, J. M., Latham, D. W., Bakos, G. A., Kovacs, G., Noyes, R. W., … Hergenrother, C. W. (2007). The Mass and Radius of the Unseen M Dwarf Companion in the Single‐Lined Eclipsing Binary HAT‐TR‐205‐013. The Astrophysical Journal, 663(1), 573–582. https://doi.org/10.1086/518413

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free