Applicability of a Schmidt law to star formation in ring galaxies

Autor(en)
E. I. Vorobyov
Abstrakt

The gas hydrodynamics modeling of the Cartwheel ring galaxy is performed with the purpose to reproduce the measured intensity and radial distribution of Hα emission in the Cartwheel's disk. The star formation efficiency of ε = 0.09-0.18 is derived for an assumed Schmidt law with power index N = 1.5 and a full thickness of the Cartwheel's gas disk of z0 = 250-1000 pc, respectively. Simulations with a Schmidt law of star formation yield a higher Hα surface brightness (Σ) in the Cartwheel's inner ring as compared to the observed values. The Toomre criterion for star formation fails to account for the observed sharp drop of massive star formation (MSF) in the inner ring. Numerical simulations indicate that a large shear near/at the position of the inner ring can raise the gas threshold for star formation and suppress MSF in the Cartwheel's inner regions. Hence, the Schmidt law has to be supplemented with a shear criterion for star formation in order to reproduce the observed radial distribution of Σ in the Cartwheel's inner regions.

Organisation(en)
Forschungsplattform Internationales Erwin Schrödinger Institut für Mathematik und Physik, Institut für Astrophysik
Journal
Astronomy & Astrophysics
Band
407
Seiten
913-917
Anzahl der Seiten
5
ISSN
0004-6361
Publikationsdatum
09-2003
Peer-reviewed
Ja
Schlagwörter
ASJC Scopus Sachgebiete
Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/dc54c66a-0095-43bc-8f1a-34a1dcd2ee1b