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Title: NEW PRECISION ORBITS OF BRIGHT DOUBLE-LINED SPECTROSCOPIC BINARIES. VIII. HR 1528, HR 6993, 2 SAGITTAE, AND 18 VULPECULAE

Abstract

Improved orbital elements for four A-star double-lined spectroscopic binaries have been determined with numerous new radial velocities. Three of the four systems, HR 1528, 2 Sge, and 18 Vul, have moderately short orbital periods of 7.05, 7.39, and 9.31 days, respectively, and also have circular or nearly circular orbits. Only HR 6993 with a period of 14.68 days has a significantly eccentric orbit. The close visual companion of 2 Sge has been detected spectroscopically, and its velocity measured. The orbital dimensions (a {sub 1} sin i and a {sub 2} sin i) and minimum masses (m {sub 1} sin{sup 3} i and m {sub 2} sin{sup 3} i) of the short-period binary components all have accuracies of 0.5% or better. We determine basic properties of the individual stars and compare them with solar-abundance evolutionary tracks to estimate their masses. Half of the eight components may be synchronously or pseudosynchronously rotating.

Authors:
;  [1];  [2]
  1. Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Boulevard, Box 9501, Nashville, TN 37209 (United States)
  2. Astronomy Department and McDonald Observatory, University of Texas, Austin, TX 78712 (United States)
Publication Date:
OSTI Identifier:
22273294
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 146; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; ASTRONOMY; ASTROPHYSICS; BINARY STARS; COMPARATIVE EVALUATIONS; MASS; ORBITS; RADIAL VELOCITY; STAR EVOLUTION

Citation Formats

Fekel, Francis C., Williamson, Michael H., and Tomkin, Jocelyn, E-mail: fekel@evans.tsuniv.edu, E-mail: michael.h.williamson@gmail.com, E-mail: jt@alexis.as.utexas.edu. NEW PRECISION ORBITS OF BRIGHT DOUBLE-LINED SPECTROSCOPIC BINARIES. VIII. HR 1528, HR 6993, 2 SAGITTAE, AND 18 VULPECULAE. United States: N. p., 2013. Web. doi:10.1088/0004-6256/146/5/129.
Fekel, Francis C., Williamson, Michael H., & Tomkin, Jocelyn, E-mail: fekel@evans.tsuniv.edu, E-mail: michael.h.williamson@gmail.com, E-mail: jt@alexis.as.utexas.edu. NEW PRECISION ORBITS OF BRIGHT DOUBLE-LINED SPECTROSCOPIC BINARIES. VIII. HR 1528, HR 6993, 2 SAGITTAE, AND 18 VULPECULAE. United States. doi:10.1088/0004-6256/146/5/129.
Fekel, Francis C., Williamson, Michael H., and Tomkin, Jocelyn, E-mail: fekel@evans.tsuniv.edu, E-mail: michael.h.williamson@gmail.com, E-mail: jt@alexis.as.utexas.edu. Fri . "NEW PRECISION ORBITS OF BRIGHT DOUBLE-LINED SPECTROSCOPIC BINARIES. VIII. HR 1528, HR 6993, 2 SAGITTAE, AND 18 VULPECULAE". United States. doi:10.1088/0004-6256/146/5/129.
@article{osti_22273294,
title = {NEW PRECISION ORBITS OF BRIGHT DOUBLE-LINED SPECTROSCOPIC BINARIES. VIII. HR 1528, HR 6993, 2 SAGITTAE, AND 18 VULPECULAE},
author = {Fekel, Francis C. and Williamson, Michael H. and Tomkin, Jocelyn, E-mail: fekel@evans.tsuniv.edu, E-mail: michael.h.williamson@gmail.com, E-mail: jt@alexis.as.utexas.edu},
abstractNote = {Improved orbital elements for four A-star double-lined spectroscopic binaries have been determined with numerous new radial velocities. Three of the four systems, HR 1528, 2 Sge, and 18 Vul, have moderately short orbital periods of 7.05, 7.39, and 9.31 days, respectively, and also have circular or nearly circular orbits. Only HR 6993 with a period of 14.68 days has a significantly eccentric orbit. The close visual companion of 2 Sge has been detected spectroscopically, and its velocity measured. The orbital dimensions (a {sub 1} sin i and a {sub 2} sin i) and minimum masses (m {sub 1} sin{sup 3} i and m {sub 2} sin{sup 3} i) of the short-period binary components all have accuracies of 0.5% or better. We determine basic properties of the individual stars and compare them with solar-abundance evolutionary tracks to estimate their masses. Half of the eight components may be synchronously or pseudosynchronously rotating.},
doi = {10.1088/0004-6256/146/5/129},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 5,
volume = 146,
place = {United States},
year = {Fri Nov 01 00:00:00 EDT 2013},
month = {Fri Nov 01 00:00:00 EDT 2013}
}
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