Star Formation Laws and Thresholds from Interstellar Medium Structure and Turbulence

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

We present an analytical model of the relation between the surface density of gas and star formation rate in galaxies and clouds, as a function of the presence of supersonic turbulence and the associated structure of the interstellar medium (ISM). The model predicts a power-law relation of index 3/2, flattened under the effects of stellar feedback at high densities or in very turbulent media, and a break at low surface densities when ISM turbulence becomes too weak to induce strong compression. This model explains the diversity of star formation laws and thresholds observed in nearby spirals and their resolved regions, the Small Magellanic Cloud, high-redshift disks and starbursting mergers, as well as Galactic molecular clouds. While other models have proposed interstellar dust content and molecule formation to be key ingredients to the observed variations of the star formation efficiency, we demonstrate instead that these variations can be explained by ISM turbulence and structure in various types of galaxies.

Detaljer

Författare
Externa organisationer
  • Paris Diderot University
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Astronomi, astrofysik och kosmologi

Nyckelord

Originalspråkokänt
Sidor (från-till)L16
Tidskriftapj
Volym760
Utgivningsnummer1
StatusPublished - 2012 nov 1
PublikationskategoriForskning
Peer review utfördJa
Externt publiceradJa