Observational Evidence of Dynamic Star Formation Rate in Milky Way Giant Molecular Clouds

Understand

Star formation on galactic scales is known to be a slow process, but whether it is slow on smaller scales is uncertain.

• We cross-correlate 5469 giant molecular clouds (GMCs) from a new all-sky catalog with 256 star forming complexes (SFCs) to build a sample of 191 SFC-GMC complexes---collections of multiple clouds each matched to 191 SFCs.
• The total mass in stars harbored by these clouds is inferred from WMAP free-free fluxes.
• We measure the GMC mass, the virial parameter, the star formation efficiency $\epsilon$ and the star formation rate per free-fall time $\epsilon_{\rm ff}$.