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The Long-Term H$α$ Emission Line Variation in $α$ Eri

M. M. F. Vinicius·Nelson Vani Leister·Juan Zorec·Ronaldo Levenhagen
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Abstract

The long-term variation of the H$α$ line in $α$ Eri has 14-15 years cyclic \bbe phase transitions. The disc formation time scales, interpreted as the periods during which the H$α$ line emission increases from zero to its maximum, agree with the viscous decretion model. On the other hand, the time required for the disc dissipation ranges from 6 to 12 years which questions the viscous disc model predictions.

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M. M. F. Vinicius, Nelson Vani Leister, Juan Zorec, Ronaldo Levenhagen. 2005-09-07. The Long-Term H$α$ Emission Line Variation in $α$ Eri. https://arxiv.org/abs/astro-ph/0509180

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