2025A&A...704A.133S

Context. Recent studies indicate that the formation of planets in protoplanetary disks begins early in the embedded Class 0/I phases of protostellar evolution. The physical and chemical makeup of the embedded phase can provide valuable insights into the process of star and planet formation.
Aims. This study aims to provide a thorough overview of the various morphologies for molecular emissions observed on disk scales (≲100 au) toward nearby embedded sources.
Methods. We present high angular resolution (0_⋅^''1, ∼ 15 au) molecular line emissions for ¹²CO, ¹³CO, C¹⁸O, SO, SiO, DCN, CH₃OH, H₂CO, and c-C₃H₂ toward 19 nearby protostellar sources in the context of the Atacama Large Millimeter/submillimeter Array (ALMA) Large Program “Early Planet Formation in Embedded Disks (eDisk).”
Results. Emissions in ¹²CO are seen toward all sources and primarily trace outflowing materials. A few sources also show high-velocity jets in SiO emission and high-velocity channel maps of ¹²CO. The ¹³CO and C¹⁸O emissions are well-known tracers of high-density regions and trace the inner envelope and disk regions with clear signs of rotation seen at continuum scales. The large-scale emissions of ¹³CO also delineate the outflow cavity walls where the outflowing and infalling materials interact with each other, and exposure to UV radiation leads to the formation of hydrocarbons such as c-C₃H₂. Both DCN and CH₃OH, when detected, show compact emissions from the inner envelope and disk regions that peak at the position of the protostar. The CH₃OH emissions are contained within the region of DCN emissions, which suggests that CH₃OH traces the hot core regions. Likewise, a few sources, also display emissions in CH₃OH toward the outflow. Both SO and H₂CO show complex morphology among the sources, suggesting that they are formed through multiple processes in protostellar systems.