2025-05-26 –, Main Conference Room
Protostellar outflows originate within a few au (or less) of the forming star and may reach linear sizes of a few parsecs. As they travel through the dense infalling envelope, they push and accelerate the ambient gas, thereby injecting energy and momentum into their surroundings. This feedback may have its most important effect on the star formation process in regions within about 10,000 au of the protostar, where most of the forming star's mass reservoir resides. We present results from an ongoing survey of the environment surrounding a large sample of protostars at different evolutionary stages in the Orion A molecular cloud. This study uses new multi-line ALMA data to probe the envelope scales, and data from the CARMA-NRO Orion survey to study the larger (core and cloud) scales. We use the molecular line data to derive the angular distribution of molecular outflow momentum and energy, and obtain two-dimensional instantaneous mass, momentum, and energy ejection rate maps using a novel approach. Our results indicate that by the end of the protostellar phase, outflows will remove about 3 to 4 solar masses from the surrounding low-mass core. These high values indicate that outflows remove a significant amount of gas from their parent envelopes and cores and continuous core accretion from larger scales is needed to replenish material for star formation. Furthermore, we show that cavity opening angles, as well as the angular distribution of outflow momentum and energy increase with the protostars' evolutionary stage. This is clear evidence that protostellar outflows significantly disrupt their natal cores, ejecting a large fraction of the mass that would have otherwise fed the nascent star. Our results support the conclusion that protostellar outflows have a direct impact on how stars get their mass, and that the natal sites of individual low-mass star formation are far more dynamic than commonly accepted theoretical paradigms.
