A long-standing problem of the general paradigm of low-mass star formation is the "luminosity problem": protostars are less
luminous than theoretically predicted. One possible solution is that the accretion process is episodic. FU Orionis-type stars
(FUors) are thought to be the visible examples for objects in the high accretion state. FUors are often surrounded by massive
envelopes, which enable the disk to produce accretion outbursts and replenish the disk material. However, we have no sufficient
information on the envelope dynamics, about where and how mass transfer from the envelope to the disk happens. Here, we present
continuum and CO line observations of the young eruptive star V346 Nor obtained with ALMA. We analyze the density and velocity
structure of the circumstellar matter, and study the infall process from the envelope onto the disk in a highly accreting system.
We determine the infall rate from the envelope onto the disk a factor of few higher than the quiescent accretion rate, hinting for
a mismatch between the infall and accretion rates as the cause of the eruption.
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