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arXiv · 2101.09204

Episodic accretion in focus: revealing the environment of FU Orionis-type stars

O. Fehér·Á. Kóspál·P. Ábrahám·M. R. Hogerheijde·Ch. Brinch·D. Semenov
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Abstract

The earliest phases of star formation are characterised by intense mass accretion from the circumstellar disk to the central star. One group of young stellar objects, the FU Orionis-type stars exhibit accretion rate peaks accompanied by bright eruptions. The occurrence of these outbursts might solve the luminosity problem of protostars, play a key role in accumulating the final star mass, and have a significant effect on the parameters of the envelope and the disk. In the framework of the Structured Accretion Disks ERC project, we are conducting a systematic investigation of these sources with millimeter interferometry to examine whether they represent normal young stars in exceptional times or they are unusual objects. Our results show that FU Orionis-type stars can be similar to both Class I and Class II systems and may be in a special evolutionary phase between the two classes with their infall-driven episodic eruptions being the main driving force of the transition.

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O. Fehér, Á. Kóspál, P. Ábrahám, M. R. Hogerheijde, Ch. Brinch, D. Semenov. 2020-02-13. Episodic accretion in focus: revealing the environment of FU Orionis-type stars. https://doi.org/10.1017/s1743921319002060

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