Artículos de revistas
The role of the Galactic bar in the chemical evolution of the Milky Way
Fecha
2014Registro en:
Monthly Notices of the Royal Astronomical Society, Oxford, v. 437, p. 3688-3701, 2014
0035-8711
10.1093/mnras/stt2164
Autor
Moraes, Oscar Cavichia de
Mollá, M.
Costa, Roberto Dell' Aglio Dias da
Maciel, Walter Junqueira
Institución
Resumen
In the absence of an interaction, central bars might be the most effective mechanism for radial
motions of gas in barred spiral galaxies, which represent two-thirds of disc galaxies. The
dynamical effects induced by bars in the first few kpc of discs might play an important role in
the disc profiles in this region. In this work, a chemical evolution model with radial gas flows
is proposed in order to mimic the effects of the Milky Way bar in the bulge and inner disc.
The model is an update of a chemical evolution model with the inclusion of radial gas flows
in the disc and bulge. The exchange of gas between the cylindrical concentric regions that
form the Galaxy is modelled considering the flows of gas from and to the adjacent cylindrical
regions. The most recent data for the bulge metallicity distribution are reproduced by means
of a single and longer bulge collapse time-scale (2 Gyr) than other chemical evolution models
predict. The model is able to reproduce the peak in the present star formation rate at 4 kpc
and the formation of the molecular gas ring. The model with a bar predicts a flattening of the
oxygen radial gradient of the disc. Additionally, models with radial gas flows predict a higher
star formation rate during the formation of the bulge. This is in agreement with the most recent
observations of the star formation rate at the centre of massive barred spiral galaxies
Ítems relacionados
Mostrando ítems relacionados por Título, autor o materia.