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The Frequency of YY Orionis Objects among the T Tauri Stars*

Published online by Cambridge University Press:  12 April 2016

I. Appenzeller*
Affiliation:
Landessternwarte Königstuhl, 6900 Heidelberg, Federal Republic Germany

Extract

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A list of 24 T Tauri stars belonging to the YY Orionis subclass is presented. From a statistical analysis it is estimated that at least 75% (and possibly all) UV-excess T Tauri stars are YY Orionis stars. Since about 50% of all known T Tauri stars show a strong UV-excess, the percentage of YY Orionis stars among the T Tauri stars is estimated to be 40 - 50%. This relative high percentage is in good agreement with the present theory of the formation and early evolution of low mass stars.

Type
Part I: Young Objects
Copyright
Copyright © Veröff. Der Remeis-Sterwarte 1977

Footnotes

*

Based in part on observations collected at the European Southern Observatory, Chile and at the Observatoire de Haute Provence, France.

References

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