Using Doppler tomography we show that FS Aur-79, a near-contact close binary system with late-type active dK7e+dM3e components, has chromospheric prominences in two distinct emission regions associated with the primary star and a larger amount of chromospheric activity associated with the cooler secondary star. The line profiles, equivalent widths, and equivalent width ratios of the Hα and Hβ emission lines as a function of orbital phase further support that the majority of the chromospheric emission originates above the secondary star and near the neck region. Analysis of high-resolution spectra using the technique of broadening functions has enabled us to determine the radial velocity of the secondary star near quadratures to be approximately 224 km s−1. A Wilson–Devinney model of the system fitting the UBV light curves and radial velocities shows that there are star spots near the chromospherically active regions. Finally, the absence of Li I λ6708 in the spectra lets us put a lower limit on the age of this system to at least 500 Myr. © 2011. The American Astronomical Society. All rights reserved.
Austin, S. J.; Robertson, J. W.; De Souza, T. R.; Tycner, C.; and Honeycutt, R. K., "The Chromospheric Activity of [HH97 FS Aur-79: a Close Binary With Late-Type Active (Dk7E+Dm3E) Components" (2011). Faculty Publications - Physical Sciences. 22.