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arXiv · 1103.1378

The importance of episodic accretion for low-mass star formation

Dimitris Stamatellos·Anthony Whitworth·David Hubber
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Abstract

A star acquires much of its mass by accreting material from a disc. Accretion is probably not continuous but episodic. We have developed a method to include the effects of episodic accretion in simulations of star formation. Episodic accretion results in bursts of radiative feedback, during which a protostar is very luminous, and its surrounding disc is heated and stabilised. These bursts typically last only a few hundred years. In contrast, the lulls between bursts may last a few thousand years; during these lulls the luminosity of the protostar is very low, and its disc cools and fragments. Thus, episodic accretion enables the formation of low-mass stars, brown dwarfs and planetary-mass objects by disc fragmentation. If episodic accretion is a common phenomenon among young protostars, then the frequency and duration of accretion bursts may be critical in determining the low-mass end of the stellar initial mass function.

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Dimitris Stamatellos, Anthony Whitworth, David Hubber. 2011-03-07. The importance of episodic accretion for low-mass star formation. https://doi.org/10.1088/0004-637x%2F730%2F1%2F32

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