English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Observations of stars in the the solar vicinity show a clear tendency for oldstars to have larger velocity dispersions. This relation is called theage-velocity dispersion relation (AVR) and it is believed to provide insightinto the heating history of the Milky Way galaxy. Here, in order to investigatethe origin of the AVR, we performed smoothed particle hydrodynamic simulationsof the self-gravitating multiphase gas disks in the static disk-halopotentials. Star formation from cold and dense gas is taken into account, andwe analyze the evolution of these star particles. We find that exponents ofsimulated AVR and the ratio of the radial to vertical velocity dispersion areclose to the observed values. We also find that the simulated AVR is not asimple consequence of dynamical heating. The evolution tracks of stars withdifferent epochs evolve gradually in the age-velocity dispersion plane as aresult of: (1) the decrease in velocity dispersion in star forming regions, and(2) the decrease in the number of cold/dense/gas as scattering sources. Theseresults suggest that the AVR involves not only the heating history of a stellardisk, but also the historical evolution of the ISM in a galaxy.

Imprints of Zero-Age Velocity Dispersions and Dynamical Heating on the Age-Velocity dispersion Relation