Red Giants in the
Gaia-ESO Survey
Rodolfo Smiljanic
&
the Gaia-ESO Survey Consortium
Dep. of Astrophysics
Nicolaus Copernicus Astronomical Center
Toruń, Poland
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
TOPICS
●
The Gaia-ESO Survey
●
Targets & Scientific Goals
●
Red Giants in the Survey
●
Data Analyses and Data Releases
●
Early Results from the Sample of Giants
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO
http://www.gaia-eso.eu/
●
●
Public Spectroscopic Survey
Two Co-PIs:
G. Gilmore (IoA Cambridge, UK)
S. Randich (Obs. Arcetri, Italy)
FLAMES multi-fiber facility
at the 8m UT2/VLT
●
Aims to observe >105 Galactic
stars
● 300 nights allocated for 4 years
(+ 1?)
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO
●
●
●
Around 300 CoIs
from 90 Institutes.
Astrophysical data
products to be
released
Huge collaboration
with a huge task!
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
The FLAMES Instrument
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
The FLAMES Instrument
A Fiber positioner with two plates (FoV of 25' diameter).
● 132 fibers of 1.2 arcsec connected to Giraffe.
● 8 fibers of 1.0 arcsec connected to UVES.
●
●
●
Giraffe: medium-high resolution spectrograph
R ~ 20000
HR10, 15N, 21: λλ 533-562, 647-679, 848-900 nm
UVES: high-resolution echelle spectrograph
R ~ 47000
#580 nm set up (λλ 476-684 nm)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO
http://www.gaia-eso.eu/
●
●
●
●
●
●
All Galactic components (halo, bulge, thick and thin disks)
Sample of ~100 open clusters
Selected calibration samples
PMS, MS and Giants
OBAFGKM-types
Multiple goals!
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Scientific Goals
●
●
Formation and evolution of the Milky Way, its stars and
stellar populations.
Kinematics and abundances
Dynamical evolution
of open clusters
(birth to disruption).
● Stellar evolution.
● Halo substructures.
● Nature of the bulge.
● Formation of the thin
and thick disks.
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia is coming!
It will observe 109 stars!!! (down to I ~ 20)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
What can Gaia do?
●
109 objects (26 x 106 with V < 15, 250 x 106 with V < 18)
Positions and proper motions better than 25μas at V=15
● Parallax error of 25μas at V=15
● RV error of 15 km/s at V=17
● Thousands of OCs (mean distances to 1%)
● Observations of clusters in the LMC (~ 200 μas)
● 80 GCs (+1000 stars) within 10kpc (mean distances to 1%)
●
Discovery of 105-106 asteroids
● For stars within 200 pc, discover every Jupiter size planet with
period between 1.5 - 9 years
●
●
Spectra with R ~ 11500 of 1.5 x 108 stars with V < 17, around
870nm
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
What can we do for Gaia?
Gaia has limited spectroscopic capabilities
Final σRV ~ 1 km/s for a G5V star with V=14, σRV ~ 5 km/s
at V = 18; for hot stars σRV ~ 10 km/s at V = 16.
● Estimates of [Fe/H] and [alpha/Fe] for stars brighter than
V~12.
●
Gaia-ESO: adds the spectroscopic information.
Better RV precision.
● Detailed abundances down to V ~ 16 (UVES).
● At least [Fe/H] and [alpha/Fe] down to V~19 (Giraffe) –
possibly more elements.
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
What can we do for Gaia?
(Gilmore et al. 2012)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO Targets
1. Open Clusters
Sample of ~100 OCs
● In all phases of evolution
(~1 Myr to ~10 Gyr)
● Covering the age-[Fe/H]radial distance-mass space
● Complete members
(from OB to M-type stars)
● UVES for brighter and key
objects (down to V ~ 16.5)
● GIRAFFE for all others
(down to V ~ 19)
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO Targets
2. Field stars:
●
●
Bulge: K giants (Giraffe);
bright giants in low-extinction regions (UVES)
Halo/Thick disks: mainly turn-off stars (Giraffe)
giants in the outer disk, flare, warp, streams...
(Giraffe)
●
Thin disk: arm, inter-arm, near-bar line of sights (Giraffe only RV)
●
Solar neighborhood: >5000 FG-type stars (< 2 kpc) (UVES)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Gaia-ESO Targets
3. Calibration fields:
●
●
●
●
Gaia Benchmark Stars
(Giraffe & UVES)
CoRoT fields
(Giraffe & UVES)
Well studied OCs and GCs
(Giraffe & UVES)
Targets of other Surveys
(Giraffe & UVES)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Benchmark Stars
●
●
●
Used to validate the
analyses
Stars with fundamental
parameters
Observed by GES, or
from a spectral library
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Red Giants in GES
Old- and intermediate age open clusters (> 100 Myr)
Clump giants with UVES
● Bulge
K giants with Giraffe
● Inner disk/Bulge
Clump giants with UVES (search for metal-poor stars)
● Outer disk, halo-thick disk substructures
Bright giants with Giraffe
● Globular clusters (calibration)
UVES and Giraffe
● CoRoT fields (calibration)
UVES and Giraffe
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Analyses & Data Products
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Analyses & Data Products
WG11: Analyses of UVES spectra of FGK-type stars
co-coordinators: A. Korn (Upsala) & R. Smiljanic (CAMK)
●
●
●
●
●
●
60+ people from 20+ different institutes (14 FTEs)
Analysis of 5000+ stars (giants and dwarfs, field and clusters)
~13 different Nodes (multiple analyses)
Receive: reduced UVES spectra, photometric information, RV
and vsini.
Deliver: atmospheric parameters, abundances, equivalent
widths, chromospheric activity with errors, quality flags, and
method-to-method dispersion.
Li, C, O, Na, Mg, Al, Si, S, Ca, Ti, Cr, Ni, Zn, Y, Zr, Mo, Ce, and Dy
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Science Verification
Numbers
●
6 months of data (up to June 2012)
UVES (FGK-type stars):
● 421 stars with atmospheric parameters
271 MW / 98 OC / 52 CAL
● 147 with log g <= 3
32 MW / 74 OC / 42 CAL
Giraffe (FGK-type stars):
● ~5348 results
~845 with log g <= 3
~462 MW / ~384 CAL (GCs and Corot)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
First Public Release
UVES FGK-type
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Early Science
●
For early science, a bit of everything was observed
OCs: stellar evolution, internal kinematics, membership, PMS,
hot-stars, etc...
● GCs: stellar evolution, GC formation
● Bulge: search for metal-poor stars, inner disk chemical
composition
● Thick disk: formation, scale lengths
● Halo: substructures, peculiar stars
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Early Science
●
●
●
●
●
Stellar Evolution
with OCs
Abundances of
Li, C, N, O, and Na
Red: GES
Blue: Smiljanic 2012
Black: Smiljanic et al. (2009)
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Early Science
●
●
●
Stellar Evolution
with OCs
Li-rich giants in an OC
Help to constrain the
evolutionary stage of
these objetcs.
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Early Science
Globular clusters: abundances (anti-)correlations.
●
GCs for CAL. but also Science
●
Red giants with UVES
●
Li, C, N, O, Na, Al...
●
NGC2808:
[Fe/H] = -1.07, age = 12-13 Gyr
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013
Summary
http://www.gaia-eso.eu/
●
GES is an exciting project that will deliver a lot!!
Data and results are public!
● Semester releases of reduced data.
● First annual release of advanced data products in ~ June 2014
● Final release: Dec. 2017 or 2018 (extension?)
●
●
Products: Atmospheric parameters, abundances, chromospheric
activity, radial velocities, reduced data, auxiliary data, errors
Many opportunities, data for different goals, OCs, GCs, MW field
● OBAFGKM-type stars
● Many red giants!
●
Dig Sites of Stellar Archaeology: Giant Stars in the Milky Way, Izmir, Turkey, 4-6 Sep. 2013