• Login
    • Submit
    View Item 
    •   Repository Home
    • UT Faculty/Researcher Works
    • UT Faculty/Researcher Works
    • View Item
    • Repository Home
    • UT Faculty/Researcher Works
    • UT Faculty/Researcher Works
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    HR 8257: A Three-Dimensional Orbit And Basic Properties

    Icon
    View/Open
    2009_04_threedimensionalorbit.pdf (281.8Kb)
    Date
    2009-04
    Author
    Fekel, Francis C.
    Boden, Andrew F.
    Tomkin, Jocelyn
    Torres, Guillermo
    Share
     Facebook
     Twitter
     LinkedIn
    Metadata
    Show full item record
    Abstract
    We have used interferometric and spectroscopic observations of HR 8257 to determine a three-dimensional orbit of the system. The orbit has a period of 12.21345 days and an eccentricity of 0.2895. The masses of the F0 and F2 dwarf components are 1.56 and 1.38M(circle dot), respectively, with fractional errors of 1.4%. Our orbital parallax of 13.632 +/- 0.095 mas, corresponding to a distance of 73.4 +/- 0.6 pc, differs from the Hipparcos result by just 2% and has a significantly smaller uncertainty. From our spectroscopic observations and spectral energy distribution modeling we determine the component effective temperatures and luminosities to be T(eff)(A) = 7030 +/- 200K and T(eff)(B) = 6560 +/- 200K and L(A) = 9.4 +/- 0.3 L(circle dot) and L(B) = 4.7 +/- 0.2 L(circle dot). The primary rotates pseudosynchronously, while the secondary is not far from its pseudosynchronous rotational velocity. Although both early-F stars are slowly rotating, neither component of this close binary is an Am star. A comparison with evolutionary tracks indicates that the stars are slightly metal poor, and although the components have evolved away from the zero-age main sequence, they are both still dwarfs.
    Department
    Astronomy
    Subject
    binaries: spectroscopic
    stars: fundamental parameters
    stars:
    individual (hr 8257)
    palomar testbed interferometer
    iccd speckle observations
    close binary
    stars
    a-type stars
    spectroscopic binaries
    12 bootis
    spectral
    classification
    rotational velocities
    solar neighborhood
    tidal
    evolution
    astronomy & astrophysics
    URI
    http://hdl.handle.net/2152/34939
    Citation
    Fekel, Francis C., Andrew F. Boden, Jocelyn Tomkin, and Guillermo Torres. "HR 8257: a three-dimensional orbit and basic properties." The Astrophysical Journal, Vol. 695, No. 2 (Apr., 2009): 1527.
    Collections
    • UT Faculty/Researcher Works
    University of Texas at Austin Libraries
    • facebook
    • twitter
    • instagram
    • youtube
    • CONTACT US
    • MAPS & DIRECTIONS
    • JOB OPPORTUNITIES
    • UT Austin Home
    • Emergency Information
    • Site Policies
    • Web Accessibility Policy
    • Web Privacy Policy
    • Adobe Reader
    Subscribe to our NewsletterGive to the Libraries

    © The University of Texas at Austin

    Browse

    Entire RepositoryCommunities & CollectionsDate IssuedAuthorsTitlesSubjectsDepartmentThis CollectionDate IssuedAuthorsTitlesSubjectsDepartment

    My Account

    Login

    Information

    AboutContactPoliciesGetting StartedGlossaryHelpFAQs

    Statistics

    View Usage Statistics
    University of Texas at Austin Libraries
    • facebook
    • twitter
    • instagram
    • youtube
    • CONTACT US
    • MAPS & DIRECTIONS
    • JOB OPPORTUNITIES
    • UT Austin Home
    • Emergency Information
    • Site Policies
    • Web Accessibility Policy
    • Web Privacy Policy
    • Adobe Reader
    Subscribe to our NewsletterGive to the Libraries

    © The University of Texas at Austin