Abstract:

In this talk, I will present Atacama Large Millimeter/submillimeter
Array observations of the protostellar system HH 212, focusing on both
its infall and outflow structures. By analyzing different molecular
tracers, I explore how material is transported from the large-scale
envelope down to the central regions, as well as how it is ejected
back into the surrounding medium. On envelope scales, I will discuss
the dynamics of the collapsing material and the role of magnetic
fields in regulating this process. In particular, I will show evidence
for a velocity difference between ionized and neutral gas, suggesting
that they are not perfectly coupled. This effect provides insight into
the physical mechanisms that govern the early stages of star formation
such as ambipolar diffusion. On smaller scales, I will present a
detailed view of the outflow structure, revealing multiple components
that trace different physical processes. These include wide-angle
winds, shocked regions, and a highly collimated jet. Together, these
features illustrate how material is launched and accelerated away from
the system, and how it interacts with its environment. Overall, this
system offers a textbook-case example of the complex interplay between
infall and outflow in the earliest phases of star formation, providing
a comprehensive view of how young stars both accrete and eject
material.