EPoS Contribution
EPoS Contribution
Protostellar Luminosities and Accretion

Michael Dunham
Yale University, New Haven, CT, USA
Despite substantial attention in recent years, a detailed understanding of the protostellar mass accretion process remains lacking. The gravitational energy liberated from core collapse is radiated away as accretion luminosity, thus studies of protostellar luminosities provide a window into the details of the accretion process. I will review our current knowledge of the observed protostellar luminosity distribution from large Spitzer infrared surveys of star-forming clouds and the inability of simple, constant accretion rate models to match the observations. I will show that models based on hydrodynamic simulations that self-consistently predict variable accretion rates with episodic bursts significantly improve the match to observations. I will discuss other independent indications that the accretion process is highly variable, and I will critically review the current physical limitations of these models. Finally, I will discuss a new class of extremely low luminosity objects located in cores not detected by Spitzer and thus previously believed to be starless. The ongoing detections of these objects, some of which may be first hydrostatic cores, have important implications for our understanding of the observed luminosity distribution and the relative numbers of starless and protostellar cores.
E. Vorobyov (Vienna, Austria)
N. Evans (UT Austin, USA)
H. Arce (Yale, USA)
X. Chen (Yale, USA)
Key publication