Kinematical and chemical evolution of the galactic disk near the sun

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

36

Chemical Evolution, Galactic Evolution, Galactic Structure, Interstellar Gas, Stellar Evolution, Stellar Motions, Abundance, Gas Density, Gas Dynamics, Kinetic Energy, Metallic Stars, Star Formation Rate, Stellar Mass Accretion, Supernovae

Scientific paper

An accretion model for the kinematical and chemical evolution of the galactic disk in the solar neighborhood is presented which takes into account the detailed z structure of the disk. The evolution of the gas and stars in a cylinder perpendicular to the galactic plane is described in terms of a galactic disk built up by infalling gas which loses its turbulent energy on a free-fall time scale until it attains its presently observed velocity dispersion; an acceleration mechanism accounts for the observed increase of stellar velocity dispersion with age. The chemical evolution of the gas and stars is calculated in an instantaneous recycling approximation. The model satisfactorily reproduces the observed gravitational acceleration perpendicular to the galactic plane as well as the age dependence of stellar velocity dispersions and the vertical gradient of stellar metallicities. From considerations of the kinetic energy balance of the gas, with energy input due to supernova explosions and dissipation due to cloud-cloud collisions, it is concluded that an additional energy source, possibly large-scale fluctuations in galactic gravitational potential, is required to maintain a constant gas velocity dispersion if the star formation rate is proportional to gas density.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Kinematical and chemical evolution of the galactic disk near the sun does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Kinematical and chemical evolution of the galactic disk near the sun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Kinematical and chemical evolution of the galactic disk near the sun will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1687200

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.