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Pre-Main-Sequence A-type stars
Published online by Cambridge University Press: 02 March 2005
Abstract
Young A-type stars in the pre–main-sequence (PMS) evolutionary phase are particularly interesting objects since they cover the mass range ($\sim$1.5-4 $M_\odot$) which is most sensitive to the internal conditions inherited from the protostellar phase. In particular, they undergo a process of thermal relaxation from which they emerge as fully radiative objects contracting towards the Main Sequence. A-type stars also show intense surface activity (including winds, accretion, pulsations) whose origin is still not completely understood, and infrared excesses related to the presence of circumstellar disks and envelopes. Disks display significant evolution in the dust properties, likely signalling the occurrence of protoplanetary growth. Finally, A-type stars are generally found in multiple systems and small aggregates with lower mass companions.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
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- Contributed Papers
- Information
- Proceedings of the International Astronomical Union , Volume 2004 , Issue IAUS224 , July 2004 , pp. 69 - 79
- Copyright
- © 2004 International Astronomical Union
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