On the Time Variability of the Star Formation Efficiency

A star formation efficiency per free-fall time that evolves over the lifetime of giant molecular clouds (GMCs) may have important implications for models of supersonic turbulence in molecular clouds or for the relation between the star formation rate and H2 surface density. We discuss observational...

Full description

Saved in:
Bibliographic Details
Published inAstrophysical journal. Letters Vol. 727; no. 1; pp. L12 - jQuery1323918569255='48'
Main Authors Feldmann, R, Gnedin, N. Y
Format Journal Article
LanguageEnglish
Published United States IOP Publishing 20.01.2011
Subjects
ASTROPHYSICS, COSMOLOGY AND ASTRONOMY
CLOUDS
DENSITY
EFFICIENCY
ELEMENTS
EVOLUTION
HYDROGEN
LIFETIME
MASS
NONMETALS
PHYSICAL PROPERTIES
STAR EVOLUTION
SURFACES
TURBULENCE
Online AccessGet full text

Cover

More Information
Summary:A star formation efficiency per free-fall time that evolves over the lifetime of giant molecular clouds (GMCs) may have important implications for models of supersonic turbulence in molecular clouds or for the relation between the star formation rate and H2 surface density. We discuss observational data that could be interpreted as evidence of such a time variability. In particular, we investigate a recent claim based on measurements of H2 and stellar masses in individual GMCs. We show that this claim depends crucially on the assumption that H2 masses do not evolve over the lifetimes of GMCs. We exemplify our findings with a simple toy model that uses a constant star formation efficiency and, yet, is able to explain the observational data.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:2041-8205
2041-8213
DOI:10.1088/2041-8205/727/1/L12