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arXiv · 0908.3336

Line-profile variability from tidal flows in Alpha Virginis (Spica)

D. M. Harrington·G. Koenigsberger·E. Moreno·J. R. Kuhn
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Abstract

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.

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D. M. Harrington, G. Koenigsberger, E. Moreno, J. R. Kuhn. 2009-08-23. Line-profile variability from tidal flows in Alpha Virginis (Spica). https://doi.org/10.1088/0004-637x/704/1/813

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