Informazioni sull’evento

02/09/2018

Joint Astrophysical Colloquium

Chemical tagging, stellar ages of halo field stars and the uncertain role of atomic diffusion

Maurizio Salaris (Liverpool John Moores University - UK)

Wednesday 30/10/2019 @ 11:30, Sala IV piano Battiferro

Age-dating Milky Way stellar populations plays a major role in studies of galaxy formation and evolution. Ages of old field halo stars that represent the fossil record of galaxy formation are particularly important. Spectroscopic surveys provide effective temperature, surface gravity and photospheric composition of large samples of Milky Way stars, and these data can be used to determine stellar ages by employing stellar evolution models. However, current uncertainties on the efficiency of atomic diffusion in the interiors of low-mass metal poor stars can affect the derived afield star ages at the level of several 10%. Asteroseismic constraints on the stellar masses can potentially reduce these errors and in the limit of high accuracy can indirectly constrain the efficiency of diffusion in the interiors of these stars.