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Title: A New Orbit for the Eclipsing Binary V577 Oph

Abstract

Pulsating stars in eclipsing binary systems are unique objects for providing constraints on stellar models. To fully leverage the information available from the binary system, full orbital radial velocity curves must be obtained. We report 23 radial velocities for components of the eclipsing binary V577 Oph, whose primary star is a δ Sct variable. The velocities cover a nearly complete orbit and a time base of 20 years. We computed orbital elements for the binary and compared them to the ephemeris computed by Creevey et al. The comparison shows marginally different results. In particular, a change in the systemic velocity by −2 km s{sup −1} is suggested by our results. We compare this systemic velocity difference to that expected due to reflex motion of the binary in response to the third body in the system. The systemic velocity difference is consistent with reflex motion, given our mass determination for the eclipsing binary and the orbital parameters determined by Volkov and Volkova for the three-body orbit. We see no evidence for the third body in our spectra, but we do see strong interstellar Na D lines that are consistent in strength with the direction and expected distance of V577 Oph.

Authors:
 [1]; ;  [2];  [3]
  1. Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States)
  2. The University of Texas at Austin, McDonald Observatory, 1 University Station, C1402, Austin, TX 78712-0259 (United States)
  3. Isaac Newton Group, Apartado de Correos 321, E-38700 Santa Cruz de La Palma, Canary Islands (Spain)
Publication Date:
OSTI Identifier:
22663163
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 154; Journal Issue: 3; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; COMPARATIVE EVALUATIONS; DIAGRAMS; DISTANCE; ECLIPSE; INTERSTELLAR GRAINS; LIMITING VALUES; MASS; ORBITS; RADIAL VELOCITY; REFLEXES; STAR MODELS; THREE-BODY PROBLEM; VARIABLE STARS

Citation Formats

Jeffery, Elizabeth J., Barnes, Thomas G. III, Montemayor, Thomas J., and Skillen, Ian, E-mail: ejjeffer@calpoly.edu, E-mail: tgb@astro.as.utexas.edu, E-mail: tm@astro.as.utexas.edu, E-mail: wji@ing.iac.es. A New Orbit for the Eclipsing Binary V577 Oph. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA845B.
Jeffery, Elizabeth J., Barnes, Thomas G. III, Montemayor, Thomas J., & Skillen, Ian, E-mail: ejjeffer@calpoly.edu, E-mail: tgb@astro.as.utexas.edu, E-mail: tm@astro.as.utexas.edu, E-mail: wji@ing.iac.es. A New Orbit for the Eclipsing Binary V577 Oph. United States. doi:10.3847/1538-3881/AA845B.
Jeffery, Elizabeth J., Barnes, Thomas G. III, Montemayor, Thomas J., and Skillen, Ian, E-mail: ejjeffer@calpoly.edu, E-mail: tgb@astro.as.utexas.edu, E-mail: tm@astro.as.utexas.edu, E-mail: wji@ing.iac.es. Fri . "A New Orbit for the Eclipsing Binary V577 Oph". United States. doi:10.3847/1538-3881/AA845B.
@article{osti_22663163,
title = {A New Orbit for the Eclipsing Binary V577 Oph},
author = {Jeffery, Elizabeth J. and Barnes, Thomas G. III and Montemayor, Thomas J. and Skillen, Ian, E-mail: ejjeffer@calpoly.edu, E-mail: tgb@astro.as.utexas.edu, E-mail: tm@astro.as.utexas.edu, E-mail: wji@ing.iac.es},
abstractNote = {Pulsating stars in eclipsing binary systems are unique objects for providing constraints on stellar models. To fully leverage the information available from the binary system, full orbital radial velocity curves must be obtained. We report 23 radial velocities for components of the eclipsing binary V577 Oph, whose primary star is a δ Sct variable. The velocities cover a nearly complete orbit and a time base of 20 years. We computed orbital elements for the binary and compared them to the ephemeris computed by Creevey et al. The comparison shows marginally different results. In particular, a change in the systemic velocity by −2 km s{sup −1} is suggested by our results. We compare this systemic velocity difference to that expected due to reflex motion of the binary in response to the third body in the system. The systemic velocity difference is consistent with reflex motion, given our mass determination for the eclipsing binary and the orbital parameters determined by Volkov and Volkova for the three-body orbit. We see no evidence for the third body in our spectra, but we do see strong interstellar Na D lines that are consistent in strength with the direction and expected distance of V577 Oph.},
doi = {10.3847/1538-3881/AA845B},
journal = {Astronomical Journal (Online)},
number = 3,
volume = 154,
place = {United States},
year = {Fri Sep 01 00:00:00 EDT 2017},
month = {Fri Sep 01 00:00:00 EDT 2017}
}
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