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After a short introduction describing the whys and wherefores of the recent and growing interaction between Milky Way physicists, stellar evolution physicists, chemical abundances physicists, and asteroseismologists, which forms the ground of this workshop, we address some important points affecting the levels of accuracy on global stellar parameters, such as mass, radius, and age, which were raised during the final discussion of the workshop. We recall how asteroseismic parameters, especially when coupled with spectroscopy and photometry, greatly help to reduce uncertainties. We show how poorly known physical aspects, such as diffusion, rotation, and outer physical conditions, must however be kept in mind when assessing these uncertainties. We then summarise the huge advance in terms of spectroscopic follow-up of seismic targets that took place in the last couple of years opening the doors for the first results in Galactic Archaeology making use of seismic distances, masses, radii, and ages. We conclude by presenting two tables: (1) an update of the table of uncertainties built at the Sesto workshop in 2013, and (2) a similar table with what should be reached for Galactic Archaeology purposes. [ABSTRACT FROM AUTHOR]

Galactic Archeology is a coined term to describe the fact that the Milky Way's history is encoded both in the amounts of various chemical elements seen in the spectra of stellar atmospheres (abundances), and in stellar motions. One of the pillars of Galactic Archaeology is the use of stellar abundance ratios as an indirect age estimator, which although imprecise, has been proved useful in providing relative ages between the different galactic components. The lack of more precise age determination for large samples of field stars is one of the main reasons why different scenarios for the formation of our Galaxy can still be accommodated to current observational constraints, thus preventing a clear picture of the Milky Way's assembling history. Another difficulty is that most of the available information (especially on ages) has been confined to a region close to the Sun. These two main obstacles can now start to be overcome thanks to a) large spectroscopic and photometric surveys covering larger portions of the Milky Way, and b) the combination of the photometric and spectroscopic information with that coming from asteroseismology. The latter promises a breakthrough in the field of Galactic Archaeology, as it brings the opportunity to, for the first time, measure ages for large samples of distant field giant stars, which cover a large age-baseline. When combining this information with that soon available from Gaia, the field of Galactic Archaeology will be shaken and modelers will certainly have less flexibility in finding models that comply to these precious new observational constraints. The goal of these short lectures is to put Asteroseismology in the context of Galactic Archaeology. [ABSTRACT FROM AUTHOR]

Our understanding of how the Galaxy was formed and evolves is severely hampered by the lack of precise constraints on basic stellar properties such as distances, masses and ages. Here, we show that solar-like pulsating red giants represent a well-populated class of accurate distance indicators, spanning a large age range, which can be used to map and date the Galactic disc in the regions probed by observations made by the CoRoT1 and Kepler space telescopes. When combined with photometric constraints, the pulsation spectra of such evolved stars not only reveal their radii, and hence distances, but also provide well-constrained estimates of their masses, which are reliable proxies for the ages of the stars. As a first application, we consider red giants observed by CoRoT in two different parts of the Milky Way, and determine precise distances for ∼2000 stars spread across nearly 15 000 pc of the Galactic disc, exploring regions which are a long way from the solar neighbourhood. We find significant differences in the mass distributions of these two samples which, by comparison with predictions of synthetic models of the Milky Way, we interpret as mainly due to the vertical gradient in the distribution of stellar masses (hence ages) in the disc. In the future, the availability of spectroscopic constraints for this sample of stars will not only improve the age determination, but also provide crucial constraints on age–velocity and age–metallicity relations at different Galactocentric radii and heights from the plane. [ABSTRACT FROM AUTHOR]