The Luminosity Problem: Testing Theories of Star Formation

TL;DR

This paper investigates why low-mass protostars are less luminous than expected, testing star formation theories by analyzing protostellar luminosity functions and collapse models.

Contribution

It evaluates different star formation models against observed luminosity data, highlighting the roles of slow formation and episodic accretion.

Findings

Stars may form slowly, aligning with recent data.

Episodic accretion explains less than half of the luminosity discrepancy.

Collapse models show varying impacts on protostellar luminosity.

Abstract

Low-mass protostars are less luminous than expected. This luminosity problem is important because the observations appear to be inconsistent with some of the basic premises of star formation theory. Two possible solutions are that stars form slowly, which is supported by recent data, and/or that protostellar accretion is episodic; current data suggest that the latter accounts for less than half the missing luminosity. The solution to the luminosity problem bears directly on the fundamental problem of the time required to form a low-mass star. The protostellar mass and luminosity functions provide powerful tools both for addressing the luminosity problem and for testing theories of star formation. Results are presented for the collapse of singular isothermal spheres, for the collapse of turbulent cores, and for competitive accretion.