Work

Series of core collapse numerical simulations (SOLANUM)

Year: 2026

Type: article

Abstract: Context . Magnetohydrodynamical simulations and interferometric observations toward young stellar objects have revealed the accretion of gas that may alter the physical properties and chemical composition of protostellar disks. Aims . Our goal is to constrain the physical history and properties of late infalling gas and assess its potential to change the physical and chemical properties of the disk. Methods . We carried out a core collapse simulation of 5 M ⊙ of gas endowed with tracer and sink particles during ∼3.6 × 10 5 yr. We analyzed the properties of the rotationally supported disk and the origin and physical history of the gas from which it initially formed. We also selected the tracer particles that describe the late infall to analyze their origin and physical history and compared them to the information obtained from the disk. Results . The final mass of the sink reaches 1.02 M ⊙ , while the mass of the disk stays fairly constant around 0.02 M ⊙ . Throughout its evolution, the disk radius increased up to ∼40 au, and its density was reduced by a factor of approximately eight. Filaments that channel gas from the envelope to the disk and sink appeared as a result of the magnetic interchange instability. Tracer particles were used to identify late infalling gas, whose physical properties resemble those of observed streamers, and they are only accreted in the final snapshots of the simulation. The origin and physical history of the late infalling gas are different from those of the gas that initially forms the disk. Conclusions . Our core collapse simulation of young stellar objects predicts the appearance of filaments that connect the envelope to the disk. The late accretion of gas through these channels has properties similar to those of streamers and brings gas to the disk with a different physical history that could translate into a different chemical composition.

Source: Astronomy and Astrophysics

DOI: 10.1051/0004-6361/202660936