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The 9 Aurigae System

K. Krisciunas·C. Aspin·T. R. Geballe·H. Akazawa·C. F. Claver·E. F. Guinan·H. J. Landis·K. D. Luedeke·N. Ohkura·O. Ohshima·D. R. Skillman
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Abstract

The F0 V star 9 Aur A exhibits an irregular variability of amplitude $\approx $0.1 magnitude at optical wavelengths. The variations are too slow for it to be a $δ$ Scuti-type star. There is no evidence for a close, interacting companion or ring of dust, either from infrared, ultraviolet, or speckle data. The photometric variability of 9 Aur A is similar to two other early F dwarf stars: $γ$ Doradus and HD 96008. 9 Aur B appears to be an M dwarf, 9 Aur C is an early- to mid-K dwarf star, and 9 Aur E, if it is a member of the system, probably is a normal white dwarf. 9 Aur D is most likely an unrelated and distant K giant. [See note added in press regarding a fourth member of this class of ``variables without a cause", and short term variations of the radial velocity of 9 Aur.]

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K. Krisciunas, C. Aspin, T. R. Geballe, H. Akazawa, C. F. Claver, E. F. Guinan, H. J. Landis, K. D. Luedeke, N. Ohkura, O. Ohshima, D. R. Skillman. 1993-04-07. The 9 Aurigae System. https://doi.org/10.1093/mnras%2F263.3.781

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