• Composite spectra - Paper 1: HR 6902

    • Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/joaa/007/03/0195-0223

    • Keywords

       

      composite spectra— spectroscopic binaries—stellar masses—stars; individual

    • Abstract

       

      Composite-spectrum binary stars generally consist of a late-type giant and a main-sequence star of type A or B. Their spectra are therefore rather confusing; but by a technique of digital subtraction of the spectra of appropriate single late-type giants, composite spectra can be split into their individual components. In favourable cases the radial velocities of both components can be measured and the mass ratio determined. The procedures are illustrated by reference to HR 6902, a fifth-magnitude composite-spectrum binary. Its components are shown to have spectral types of G9 II and B8 V, with a mass ratio of 1.31, and its orbit is determined. There is some evidence that the system shows eclipses. If it does, the masses of the components are 3.9 and 3.0M⊙ respectively, and HR 6902 becomes the sixth known member of the important class ofζ Aur binaries.

    • Author Affiliations

       

      R. & R. Griffin1 2

      1. The Observatories, Madingley Road, Cambridge - CB3 0HA, England
      2. Visiting Associates Mount Wilson & Las Campanas Observatories, Carnegie Institution of Washington, Cambridge - CB3 0HA, England
    • Dates

       
  • Journal of Astrophysics and Astronomy | News

    • Continuous Article Publication

      Posted on January 27, 2016

      Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.