From clouds to protostars (and then back to the cloud): studying the early stages of star formation and stellar feedback

Héctor Arce, Yale University

Nearly all stages of protostellar evolution have been observed in large samples and compared to theoretical predictions. However, one of the very early stages, commonly known as the first hydrostatic core (FHSC) stage, remains unobserved. This very early phase lies between the prestellar and protostellar phases and is an important stage in the star formation process where infall and outflow motions in the core may affect the final mass of the forming star (and in some cases the existence of multiple stellar companions). I will present results on the study of a sample of FHSC candidates and deeply embedded multiple systems and discuss how these help us better understand the early evolutionary stages of protostars. Furthermore, I will discuss the importance of protostellar outflows and their impact on molecular cloud turbulence, gas dispersal and the cloud's star formation efficiency.