Pisa, 4 May 2009 Alessandro Spagna A new kinematic survey (from GSC-II and SDSS-DR7) to study the stellar populations of the Milky Way Alessandro Spagna 1 , Beatrice Bucciarelli 1 , Mario Lattanzi 1 , Paola Re Fiorentin 2 , Richard Smart 1 (1 - INAF-OATo, 2 – Univ. of Ljubljana)
A new kinematic survey (from GSC-II and SDSS-DR7) to study the stellar populations of the Milky Way. Alessandro Spagna 1 , Beatrice Bucciarelli 1 , Mario Lattanzi 1 , Paola Re Fiorentin 2 , Richard Smart 1 (1 - INAF-OATo, 2 – Univ. of Ljubljana). - PowerPoint PPT Presentation
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Pisa, 4 May 2009 Alessandro Spagna
A new kinematic survey (from GSC-II and SDSS-DR7)
to study the stellar populations of the Milky Way
Alessandro Spagna1, Beatrice Bucciarelli1, Mario Lattanzi1, Paola Re Fiorentin2, Richard Smart1
** Kinematic sample: 4500<Teff<7500 K, log g >3.5, [Fe/H]< -0.5, d < 3 kpc
Pisa, 4 May 2009 Alessandro Spagna
Kinematics & Chemical properties: overview
Pisa, 4 May 2009 Alessandro Spagna
Kinematics & Chemical properties: overview
Pisa, 4 May 2009 Alessandro Spagna
From Re Fiorentin et al (2005)
Kinematics & Chemical properties: stellar streams
Pisa, 4 May 2009 Alessandro Spagna
Kinematics & Chemical properties: overview
-1< [Fe/H] < -0.5
-1.0< [Fe/H] < -1.5
Pisa, 4 May 2009 Alessandro Spagna
Kinematics & Chemical properties: overview
-2.0< [Fe/H] < -1.5
[Fe/H] < -2.0
Pisa, 4 May 2009 Alessandro Spagna
CONCLUSIONS
• We have produced a new proper motion survey covering 9000 deg2 based on the multi-epoch positions derived SDSS – DR7 combined with the plate material from the GSC-II database.
• Accurate absolute proper motions (µ,µ) have been computed for 40 million sources down to magnitude g~22 (r~20). Proper motion errors attain 2-3 mas/yr.
• Stellar astrophysical parameters (Teff, log g, [Fe/H] ) have been (re)estimated for the SDSS spectroscopic sample by means of updated ANN methods.
• Full astrometric, photometric, and spectroscopic measurements are available for 150,000 stars.
• Photometric distances and 3D velocities (UVW) have been computed for FGK (sub)dwarfs with [Fe/H]< -0.5.
• A kinematic sample of 30,700 tracers within 3 kpc from the Sun has been extracted and will be used to (1) study the kinematic properties of the thick disk and inner halo and (2) search for members of known/new kinematic substructures produced by past merging events.