Spiral stellar density waves and the flattening of abundance gradients in the warm gas component of spiral galaxies

Autor(en)
E. I. Vorobyov
Abstrakt

Motivated by recent observations of plateaus and minima in the radial abundance distributions of heavy elements in the Milky Way and some other spiral galaxies, we propose a dynamical mechanism for the formation of such features around corotation. Our numerical simulations show that the non-axisymmetric gravitational field of spiral density waves generates cyclone and anticylone gas flows in the vicinity of corotation. The anticyclones flatten the pre-existing negative abundance gradients by exporting many more atoms of heavy elements outside corotation than importing inside it. This process is very efficient and forms plateaus of several kiloparsec in size around corotation after two revolution periods of a galaxy. The strength of anticyclones and, consequently, the sizes of plateaus depend on the pitch angle of spiral arms and are expected to increase along the Hubble sequence.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
University of Toronto, University of Western Ontario
Journal
Monthly Notices of the Royal Astronomical Society
Band
370
Seiten
1046-1054
Anzahl der Seiten
9
ISSN
0035-8711
DOI
https://doi.org/10.1111/j.1365-2966.2006.10550.x
Publikationsdatum
08-2006
Peer-reviewed
Ja
ÖFOS 2012
103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/b6d12152-91c5-4bb4-8d83-cd2312210fbb