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arXiv · 2111.12723

On the rise times in FU Orionis events

Elisabeth M. A. Borchert·Daniel J. Price·Christophe Pinte·Nicolás Cuello
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Abstract

We examine whether stellar flyby simulations can initiate FU Orionis outbursts using 3D hydrodynamics simulations coupled to live Monte Carlo radiative transfer. We find that a flyby where the secondary penetrates the circumprimary disc triggers a 1-2 year rise in the mass accretion rate to $10^{-4}~{\rm M_{\odot}~ yr^{-1}}$ that remains high ($\gtrsim 10^{-5}~{\rm M_{\odot}~yr^{-1}}$) for more than a hundred years, similar to the outburst observed in FU Ori. Importantly, we find that the less massive star becomes the dominant accretor, as observed.

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Elisabeth M. A. Borchert, Daniel J. Price, Christophe Pinte, Nicolás Cuello. 2021-11-24. On the rise times in FU Orionis events. https://doi.org/10.1093/mnrasl%2Fslab123

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