ALMA observations of the FU Orionis-type young eruptive star V346 Nor
- Dr. Ágnes KÓSPÁL
- Dr. Ágnes KÓSPÁL (Konkoly Observatory)
A long-standing problem of the general paradigm of low-mass star formation is the "luminosity problem": protostars are less luminous than theoretically predicted. A possible solution is that the accretion process is episodic. FU Ori-type stars (FUors) are thought to be the visible examples for objects in the high accretion state. FUors are often surrounded by massive envelopes, enabling the disk to produce accretion outbursts and replenish the disk material. However, we have no information on the envelope dynamics, about where and how mass transfer from the envelope to the disk happens. We used ALMA to observe the envelope of a carefully selected FUor, V346 Nor, in different CO lines and mapped its density and velocity structure. We analyzed the observations using our modeling environment including a combination of chemical, hydrodynamical, and radiative transfer calculations, which can model both the infall process and the disk accretion. This will enable us to measure the infall rate in the envelopes and calculate how often the object can produce repetitive outbursts. The results will help us to decide whether FUor-type eruptions can really be the solution to the luminosity problem.