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DOE OSTI · 22520089

LAMBDA BOO ABUNDANCE PATTERNS: ACCRETION FROM ORBITING SOURCES

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Abstract

The abundance anomalies in λ Boo stars are popularly explained by element-specific mass inflows at rates that are much greater than empirically inferred bounds for interstellar accretion. Therefore, a λ Boo star’s thin outer envelope must derive from a companion star, planet, analogs to Kuiper Belt objects or a circumstellar disk. Because radiation pressure on gas-phase ions might selectively allow the accretion of carbon, nitrogen, and oxygen and inhibit the inflow of elements such as iron, the source of the acquired matter need not contain dust. We propose that at least some λ Boo stars accrete from the winds of hot Jupiters.

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79 ASTRONOMY AND ASTROPHYSICSCARBONCOSMIC DUSTELEMENT ABUNDANCEINTERSTELLAR SPACEIRONMASSNITROGENOXYGENRADIATION PRESSURESTAR ACCRETIONSTARSSTELLAR WINDS

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2015-12-15. LAMBDA BOO ABUNDANCE PATTERNS: ACCRETION FROM ORBITING SOURCES. https://doi.org/10.1088/0004-6256%2F150%2F6%2F166

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