Lambda Boötis star

A Lambda Boötis star is a type of peculiar star which has an unusually low abundance of iron peak elements in its surface layers. One possible explanation for this is that it is the result of accretion of metal-poor gas from a circumstellar disc, a second possibility is the accretion of material from a hot Jupiter suffering from mass loss. The prototype is Lambda Boötis.^[1]

References

• Paunzen, Ernst (2004). "The λ Bootis stars". In Zverko, J.; Ziznovsky, J.; Adelman, S.J.; Weiss, W.W. The A-Star Puzzle. IAU Symposium, No. 224. ISBN 0521850185. Retrieved 2008-11-16. 
• Gray, R.O.; Corbally, C.J. (2002). "A Spectroscopic Search for λ Bootis and Other Peculiar A-Type Stars in Intermediate-Age Open Clusters". The Astronomical Journal. 124 (2): 989–1000. Bibcode:2002AJ....124..989G. doi:10.1086/341609. 

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Evolution	Formation Pre-main-sequence star Main sequence Red giant branch Horizontal branch Asymptotic giant branch Dredge-up Instability strip Red clump PG1159 star Mira variable Planetary nebula Protoplanetary nebula Luminous red nova Luminous blue variable Wolf–Rayet star Stellar population Supernova Supernova impostor Hypernova Hertzsprung–Russell diagram Color–color diagram
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Related articles	Substellar object Brown dwarf Sub-brown dwarf Planet Galactic year Galaxy Supercluster Helioseismology Guest star Constellation Asterism Gravity Intergalactic star Infrared dark cloud Starfield
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