Where are we now and where are we going? Arlette Noels & Josefina Montalbán

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1 Where are we now and where are we going? Arlette Noels & Josefina Montalbán

2 Formation & Evolution MW AMR V R AR Stellar Models AGE Asteroseismology Spect. & Photom. surveys logg M, R, d Π, μ, σ, Teff chemic. comp.

3 huge number of giants N Comparison CoRoT/Trilegal N A. Miglio et al.: Probing populations of red giants in the galactic disk with CoRoT L23 Probing populations of red giants in the galactic disk with CoRoT T1 Trilegal T A. Miglio 1,,J.Montalbán 1,F.Baudin 2 300,P.Eggenberger 1,3,A.Noels 1,S.Hekker 4,5,6,J.DeRidder 5, T1 W. Weiss 7,andA.Baglin T1 N N July T1 T2 Trilegal N CoRoT ν (µhz) max νmax Fig. 3. Histogram showing the comparison between the ν max distribution of the observed (lower panel) andsimulatedpopulationsofredgiants: N N T2 CoRoT ν (µhz) Δν Fig Histogram showing the comparison between thecorot ν distribution of the observed (lower panel) andsimulatedpopulationsofredgiants: 3

4 Red Giants as probes of the structure and evolution of the MW Stellar ev. models A. Weiss M. Salaris P. Eggenberger S. Cassisi C. Charbonnel A. Palacios (A.Miglio J. Montalban, A. Noels) Rome, Nov Atm. & chemic. abund. H. Ludwig B. Plez M. Valentini R. Gratton Seismology W. Dziembowski B. Mosser Stellar Pop. & Models of MW L. Girardi K. Freeman C. Chiappini A. Robin

5 35 participants

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7 40 participants 7

8 592. WE-Heraeus-Seminar 1st to 5th June 2015 Reconstructing the Milky Way s History: Spectroscopic Surveys, Asteroseismology and Chemodynamical Models Venue: Physikzentrum Bad Honnef Hauptstraße Bad Honnef (near Bonn, Germany) 70 participants 8

9 1. Formation & Evolution MW AMR V R AR Stellar Models AGE Asteroseismology Spect. & Photom. surveys logg M, R, d Π, μ, σ, Teff chemic. comp.

10 1. Stellar models and asteroseismology

11 Grids of stellar models Dwarfs Pisa stellar models - X, Z, M, Te, L, Δν, νmax M ± 4.5 % R ± 2.2 % Age % Fe/H 40 % of the error budget Extreme grids - ΔY/ΔZ negligible effect on age - lmlt ( ) Age bias % - Diffusion Age bias 40 % - αe-m Age bias - 7 % (α=0.2) - 13 % (α=0.4) But internal errors Garstec grids - X, Z, M, Te, L, Δν, νmax M ± 5.5 % R ± 2.2 % Age 25 %, ν M ± 3.3 % R ± 1.1 % Age 15 %

12 L, Te, [Fe/H] + Δν + Δν, νmax + Δν, νmax, νi Case Observed Adjusted Fixed 1 T eff, L,[Fe/H] A, M, (Z/X) 0 α conv, Y 0 2a, b, c T eff, L,[Fe/H], ν A, M, (Z/X) 0, α conv Y 0 3 T eff, L,[Fe/H], ν, ν max A, M, (Z/X) 0, α conv, Y 0 4 T eff, L,[Fe/H], ν, d 02 A, M, (Z/X) 0, α conv, Y 0 5 T eff, L,[Fe/H], r 02, rr 01/10 A, M, (Z/X) 0, α conv, Y 0 6 T eff, L,[Fe/H], r 02 (n), rr 01/10 (n) A, M, (Z/X) 0, α conv, Y 0 7 T eff, L,[Fe/H], ν n,l A, M, (Z/X) 0, α conv, Y 0 ageandmass. Fig. 4. Ranges of ages (left) andmasses(right) derivedfromstellarmodeloptimizationforhd as defined in Table 3. Foreachcase,severalmodeloptimizationscanbeidentifiedaccordingtothesy addition, open red symbols are for additional models of set A described in Table A.1 of Appendix A Set Input physics Figure symbol/colour A REF circle, cyan B convection MLT square, orange C AGSS09 mixture diamond, blue D NACRE for 14 N(p, γ) 15 O smalldiamond, magenta E no microscopic diffusion pentagon, red F Kurucz model atmosphere, MLT bowtie, brown G B69 for microscopic diffusion upwards triangle, chartreuse H EoS OPAL01 downwards triangle, purple I overshooting α ov = 0.15H P inferior, yellow J overshooting M ov,c = 1.8 M cc superior, gold K convective penetration ξ PC = 1.3H P asterisk, pink square and diamond are for low and high α conv values, small diamonds for models with large core o degeneracy in cases 6 and 7, but the inferred range is the same for all cases. abundance (Y P = 0.245) and the model with low α conv = The ages of the other models are concentrated in a narrow age interval, Gyr,aboutthatofreferencemodelA. We point out that if the error bars on the classical parameters were to be reduced, as will be the case after the Gaia-ESA and 2.22 ± 0.27 Gyr (mo 0.35 Gyr, that is an age un For case 5, considerin Lebreton input physics & Goupil, 2014, of the A&Astell excluded because their in

13 What do we (don t) know for sure about stellar physics? Diffusion - is diffusion inhibited or not?? - if yes, to which extent? In which mass range? - radiative acceleration at low Z only?? Age reduction 40 % Rotation - problems with the helioseismic rotation profile - problems with the rotation contrast in RG - unknown process to transport angular momentum - would it be better to ignore rotation? Age spread 40 % Outer boundary conditions - effects still not well understood - 3D models can certainly help

14 Solar models for different atmospheric models adopted to obtain the outer boundary conditions δteff K E. Tognelli, P. G. Prada Moroni, S. Degl Innocenti, 2011, A&A, 533, A109

15 Age? % Dwarfs Semiconvection? Rotation + 40 % Diffusion - 40 % Rotation inhibits diffusion + 40 % No rotation diffusion - 40 % } 40 % lmlt % Te? L? νmax Δν/5 (/4, /3??) Calibration of the scaling relation? ~100 %

16 First good news : ages of low mass RG are much more robust than ages of low mass dwarfs

17 Diffusion : 40 % MS MS Rotation : 40 % MS Diffusion : 5 % RG Rotation : a few % RG RG tight (age,mass) relation especially if Z is known Miglio et al Miglio et al. 2012

18 Second good news : There is still work to be done in stellar evolution! Importance of model comparison different codes different time steps

19 The importance of being cluster st A case project for K2? A case project for PLATO? A case project for a dedicated new space mission Stellar population synthesis Models? SFR? AMR? Mass distribution Radius distribution? 19

20 Formation & Evolution MW AMR V R AR Stellar Models AGE Asteroseismology Spect. & Photom. surveys logg M, R, d Π, μ, σ, Teff chemic. comp. 2.

21 2. Spectroscopic and photometric surveys

22 RAVE Gaia-ESO APOGEE GALAH Gaia LAMOST SAGA 4Most WEAVE APOKASC COROGEE CoRoT-GESS

23 Spectroscopic surveys challenges: one or multi pipelines? how to manage the procedures and uncertainties computation for both choices necessity : understand the needs from stellar modelers and from spectroscopic surveys

24 What precision do we need on Fe/H, Xi, M, R, age,? Stellar models Formation & evolution of the galaxy thick disk/thin disk AMR An uncertainty of 25 % on the age is required from sismo What is the precision required on Z from spectro surveys? 24

25 Sesto table Where are we NOW? Property Uncertainty R 5 % M 10 % Te K (Z ) 2 - >>> at low Z log g dex 2 L depends on Π (Gaia), BC 4 Y Y,Helio = ± Z Z = age 40 % 1-20 % if Z and ev state are known αe-m? α MLT? 1 From scaling relations (see A. Miglio, J. Montalban and D. Stello, Sesto proceedings) 2 T. Morel, private communication (see also T. Morel, Sesto proceedings) 3 Molenda-Zakowicz et al. 2013, MNRAS 434, Bruntt et al. 2010, MNRAS 405, M. Asplund et al., see the discussion in Sesto proceedings

26 «Galactic»table What would we like? Property Uncertainty R % M % Te log g dex L Π (Gaia) Y Y = Y,Helio +? [Fe/H] [Fe/H] = 0.05 dex [α/fe] [α/fe] = «good age» 30 %? VR?

27 How do we organize ourselves? CoRoT Kepler K2 PLATO RAVE Gaia-ESO APOGEE GALAH Gaia LAMOST SAGA 4Most WEAVE APOKASC COROGEE CoRoT-GESS

28 CoRoT targets still to be delivered LR01 LR02 LR03 LR04 LR05 LR06 LR07 LR08 LR09 LR10 CoRoT targets with Ks < 11 and 0.7 < J Ks < 1.1 N Anticentre Centre

29 K2 fields

30 See you soon! 30