Spectrographic observations of the eclipsing binaries of the W Ursae Majoris type, AH Virginis and TZ Bootis.

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view Abstract Citations References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Spectrographic observations of the eclipsing binaries of the W Ursae Majoris type, AH Virginis and TZ Bootis. Chang, Y. C. Abstract Over 30 spectrograms for each of these eclipsing binaries have been obtained at the McDonald Observatory with a dispersion of 76 A/mm at H~. The spectral lines of AH Vir break up into components at quadrature. The difference in intensity of the components is greatest at phase 0.75 P and is least at phase 0.25 P. Assuming a ~ircular orbit, it has been found from the velocity curve that ~ = QIo km/sec; Kb = 105 km/sec; = 250 km/sec. In many respects, the spectroscopic behavior of this binary bears close resemblance to YY Eri, another eclipsing variable of the W Ursae Majoris type. The mass-functions are mbSin3i = i.~~.and m~S~~3~ = 0.56. It appears to be fairly general that the mass ratio as given by Kb and Kf differs from unity by a greater amount than can be reconciled with the mass-luminosity relation. The spectral lines of TZ Boo do not become double at quadrature. There does not seem to be any correlation between the radial velocity and phase as calculated from the period of light variation. The mean velocity is - ~8 km/sec. Yerkes Observatory, Williams Bay, Wis. Publication: The Astronomical Journal Pub Date: February 1948 DOI: 10.1086/106066 Bibcode: 1948AJ.....53..111C full text sources ADS |