We present the results of high precision, high resolution (R~68000) optical observations of the short-period (4d) eccentric binary system Alpha Virginis (Spica) showing the photospheric line-profile variability that in this system can be attributed to non-radial pulsations driven by tidal effects. Although scant in orbital phase coverage, the data provide S/N>2000 line profiles at full spectral resolution in the wavelength range delta-lambda = 4000--8500 Angstroms, allowing a detailed study of the night-to-night variability as well as changes that occur on ~2 hr timescale. Using an ab initio theoretical calculation, we show that the line-profile variability can arise as a natural consequence of surface flows that are induced by the tidal interaction.
@article{arxiv.0908.3336,
title = {Line-profile variability from tidal flows in Alpha Virginis (Spica)},
author = {D. M. Harrington and G. Koenigsberger and E. Moreno and J. R. Kuhn},
journal= {arXiv preprint arXiv:0908.3336},
year = {2015}
}
Comments
Accepted in ApJ, Version 2 reformatted figure layout