Gaia-ESO survey

The Gaia-ESO Survey (GES) is a large public spectroscopic survey approved in 2011 on a competitive basis by the European Southern Observatory (ESO) public spectroscopic survey panel.gaia-eso-logo

A total of 300 nights, distributed over 5 years have been allocated to the project.

Upon completion, GES will have targeted with the spectrograph FLAMES on the Very Large Telescope (VLT) more than 105 stars, systematically covering all major components of the Milky Way (MW), including large, unbiased samples of stars in more than 50 open clusters (OC). It is bringing us into a new domain of cluster research.

GES will represent the largest cluster survey so far carried out (in terms of both number and variety of OCs and stars), providing the first homogeneous overview of the distributions of kinematics, stellar parameters, and elemental abundances.

GES is obtaining GIRAFFE and UVES spectra that will:

  1. quantify astrophysical parameters (effective temperature and surface gravity), metallicity ([Fe/H]), and individual elemental abundances;
  2. yield precise radial velocities (RVs);
  3. map kinematic gradients and abundance throughout the Galaxy;
  4. provide a legacy dataset that adds enormous value to the Gaia mission and ongoing imaging surveys.

GES will not only supply homogeneously determined stellar parameters, element abundances, and RVs, but also stellar rotation rates, and diagnostics of magnetic activity, accretion, and mass loss for large samples of members of OCs.

This information can be used to challenge models of stellar structure and evolution, as well as to test models of rotational evolution and mass accretion from circumstellar discs into the star. GES is a very large collaboration involving more than 400 researchers, mostly (but not only) in Europe.

The Co-PIs are Gerry Gilmore (responsibility of MW subprogram me) and Sofia Randich (responsibility of OC subprogram me);


Partner internazionali/nazionali:

  • European Southern Observatory
  • University of Cambridge,
  • INAF ,
  • più molti altri istituti principalmente europei

Ruolo di OAPA e partecipanti

The OAPA is strongly involved in the open cluster subprogram, in particular devotes significant effort to young cluster and target selection, target allocation and preparation of observations and verification.

In addition, its researchers contribute to the spectral line analysis and characterization, astrophysical parameter derivation, and analysis of chromospheric activity in both clusters and MW field stars. Whilst stellar parameters are provided both for the OC and MW targets, the OAPA researchers are particularly focused on the analysis of very young OC stars. In particular, accurate determination of stellar ages and masses is bound on accurate astrophysics parameter derivation and this is a challenging task for very young stars, characterized by very complex properties, such as accretion and variable reddening. In addition, they are involved in the emission line analysis of GES spectra of young stars that provide precious information on their accretion status, as well as the study of the nebular lines in young star forming regions, crucial to understand the gas dynamics from which the stars formed.

Partecipants: Giusi Micela (steering commettee member), Francesco Damiani (GES builder), Ettore Flaccomio (GES builder), Loredana Prisinzano (GES builder), Sara Bonito, Laura Venuti, Mario Guarcello, Beate Stelzer, Laura Affer, Costanza Argiroffi.

Link(s) esterno/i

Altre informazioni ritenute importante/utili: il progetto GES e’ in parte supportato dal PRIN-INAF 2014, in cui OAPA e’ una delle unita’ di ricerca.