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Nicolas Grevesse

The Solar Chemical Composition. Nicolas Grevesse Centre Spatial de Liège and Institut d´Astrophysique et de Géophysique, Université de Liège, Belgium. Dynamical vision !!. New…dynamic sun. Old…static sun. HOW ? Photospheric spectrum - vis.+IR - absorption lines - neutral

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Nicolas Grevesse

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  1. The SolarChemical Composition Nicolas Grevesse Centre Spatial de Liège and Institut d´Astrophysique et de Géophysique, Université de Liège, Belgium

  2. Dynamical vision !! New…dynamic sun Old…static sun

  3. HOW ?Photosphericspectrum - vis.+IR - absorption lines - neutral and once ionized (T:5000K) + few molecules j i Absorption depends on ratio κline/κcont i.e. ÷(Nel/NH) • Ni* x Aji (or gifij-values) • Physical processes (LTE-NLTE) • Physical conditions :T,P=f(z)…Model Iline (W)depends * Number of atoms or ions that are in level i

  4. HT TPICS  Solar O,C  Solar Neon? Solar Fe?

  5. Solar Metallicity, Z O+C=61% of Z O+C+Fe+Ne=80% of Z C+N+O ~ 2/3 Z By Mass X+Y+Z=1 X=0.7381 Y=0.2485 Z=0.0134 Z/X=0.0181

  6. cz O Opacity inside the Sun C Ne Fe N

  7. New SolarChemical Composition (invitation from ARAA received in July 2006) Martin ASPLUND – Max-Planck-Institut für Astrophysik – Garching- Germany ; Australian National University, Canberra, Australia Nicolas GREVESSE– Centre Spatial de Liège and Institut d’Astrophysique et de Géophysique, University of Liège, Belgium A. Jacques SAUVAL – Observatoire Royal de Belgique - Brussels Pat SCOTT - Dept. of Physics – Stockholm University – Sweden; now Department of Physics, University McGill, Montreal, Canada M. Asplund, N. Grevesse, A.J. Sauval, P. Scott, Annual Rev. Astron. Astrophys. 47, 481, 2009 (AGSS)

  8. END RESULT: a COMPREHENSIVEandHOMOGENEOUSre-determination of the abundances of nearly all the elements in the sun. Such an analysishad not been donesincemanydecades!!

  9. Anders-Grevesse Grevesse-Noels Grevesse-Sauval Caffau et al. AGSS

  10. Anders-Grevesse Grevesse-Noels Caffau et al. Grevesse-Sauval AGSS

  11. Anders-Grevesse Grevesse-Noels Grevesse-Sauval Caffau et al. AGSS

  12. Re-determination of the abundances of nearly all availableelements • BASIC INGREDIENTS • New 3D model instead of the classical 1D models of the • lowersolaratmosphere • Careful and verydemandingselection of the spectral • lines… AVOID blends!!! NOT TRIVIAL!!! • Permanent CONCERN: QUALITY ratherthan QUANTITY • Carefulchoice of the atomic and molecular data • NOT TRIVIAL!!!! • NLTE instead of the classical LTE hypothesis… • WHEN POSSIBLE !!! • Use of ALLindicators (CNO: atoms as well as molecules)

  13. O I lines * Level population at 9 eV (permitted lines) is 10-9 of level population in the ground state level (forbidden lines).

  14. Molecular lines: OH vr and pr IR OH – pure rotation ~ 14.6 μm

  15. Suppose you have 109 atoms of O, how many are distributed in the lower levels to produce the very low excitation forbidden O I lines, the very high Exc (> 9 eV) permitted O I lines and the low Exc vr and pr lines of OH? Answer: [O I] ~ 109 O I ~ ONE!!! OH ~ 103to 104 (CO ~ 108) Conclusions: Forbidden lines better than OH lines themselves much better than permitted lines Important remark: MOLECULAR lines are NOT more sensitive than the high Exc ATOMIC lines to TEMPERATURE

  16. Forbidden [O I] lines LTE… BUT… 6300 blendwith Ni I line (37%) 6363 blendwithtwo CN lines (31%) 5577 blendwith C2 and CN lines (63%) Weestimated the contributions of the blendsindependently of any model, in a purelyempiricalway, from observations of otherlines of Ni I, C2 and CN

  17. [O I] 630nm line • Revised solar O abundance: log O=8.69+/-0.05 • Allende Prieto et al. (2001) • Blend with Ni: -0.13 dex • 3D-1D model: -0.08 dex Ni blend (not noticed in 1D) SOHO18/GONG2006/HELAS1 – Sheffield, August 2006

  18. Permitted O I lines High excitation lines (9.15 to 10.74 eV) LARGE NLTE effects [Δ~-0.25(F) to -0.15(I) dex] Strongly dependent on collisions with H atoms Cross sections not well known* * We estimated them from C/L observations and predictions made with different values of these cross sections

  19. Anders-Grevesse Grevesse-Noels Grevesse-Sauval Caffau et al. AGSS Why has the abundance of O decreased?

  20. Why has the abundance of O decreased? • Forbidden lines – Blends ! O down to 8.70 (model 3D - 1D ~ 0) • Permitted lines – NLTE ! O down to 8.69 (model 3D - 1D ~ 0) • Molecular lines – Model ! O down to 8.69 • GOOD AGREEMENT: LOW O • In the nineties, with 1D HM Model…(NG,JS,AN) • (AG89, GN93, GS98) • Forbidden lines - no blends - ~ 8.8-8.9 • Permitted lines - LTE - ~ 8.8-8.9 • Molecular lines – T too large - ~ 8.8-8.9 Good agreement: High O Today…(AGSS09)

  21. Oxygen Results • Discordant results in 1D: log O~8.69-8.86 • Excellent agreement in 3D: log O=8.69+/-0.05 • O isotopic abundances: 16O/18O=480+/-30 If LTE (O I): log O=8.82+/-0.10 [mean Δ(NLTE)=-0.13 dex] !!! Δ(NLTE) depends strongly on collisions with H atoms

  22. Carbon Results • Discordant results in 1D: log C~8.41-8.69 • Excellent agreement in 3D: log O=8.43+/-0.05 • C isotopic abundances: 12C/13C=87+/-4

  23. Solar CNO abundances • 3D solar model atmosphere • Non-LTE line formation when possible • Atomic and molecular lines with improved data • Blends of forbidden lines Forget about Anders-Grevesse 89,GN93, Grevesse-Sauval 98 USE AGSS09!

  24. Solar Ne abundance … Ne/O We used Ne/O=0.175 0.031 (Young, 2005; Quiet SUN) ANe = 7.93 0.17 dex (1.5x) smaller than older values • Such ‘low’ Ne/O solar values have been confirmed by • Young (2005) Quiet Sun (EUV, CDS, Soho) • Schmelz et al. (2005) Active regions (X rays) • SEP, SW, Corona at ≠ T

  25. Drake&Testa(2005)* Ne/O X-ray luminosity Solar Ne abundance New analyzes of solar neighborhood suggested that solar Ne is underestimated (Ne/O=0.3 to 0.4) We (Asplund, Grevesse, Guedel and Sauval) suggested the GREEN inclined line rather than the RED horizontal line…… *The <solar model problem> solved by the abundance of Neon in nearby stars (Nature)

  26. Drake & Testa (2005): Ne/O X-ray luminosity Solar Ne abundance Recent studies of solar neighborhood show that solar Ne is NOT underestimated ! Robrade, Schmitt & Favata (2008) (see also Liefke and Schmitt (2006))

  27. Iron from Fe I and Fe II lines Fe I 21 lines (Exc 0.1-4.6 eV) very accurate transition probabilities NLTE very small (~+0.01) very good indicator Fe II 9 lines (Exc 2.8-3.9 eV) accuracy of transition probabilities? LTE good indicator? 7.45±0.04 7.51±0.04 Mean all lines 7.47±0.04 (Meteorites 7.45) Why difference of 0.06 dex between Fe I and Fe II?

  28. (Some) Implications

  29. New solar metallicity O+C=61% of Z O+C+Fe+Ne=80% of Z C+N+O ~ 2/3 Z By Mass X+Y+Z=1 X=0.7381 Y=0.2485 Z=0.0134 Z/X=0.0181 Anders, Grevesse 1989 Z=0.020 Z/X=0.027 Grevesse, Noels 1993 Z=0.018 Z/X=0.024 Grevesse, Sauval 1998 Z=0.017 Z/X=0.023 NOTE: Uncertainty on Z: 12%... Z from 0.0118 to 0.0150 By number H  91.3%, He  8.5%,  other elements  0.15%

  30. Mean difference Sun - Meteorites 0.00 0.05 Synergies between solar and stellar modeling, Rome, 22-26 June 2009 Padova - November 21, 2007

  31. But … a grain of sand in the honeymoonbetween SSM-Helioseismology

  32. Rcz/R =0.713±0.001 Y = 0.248±0.003 Helioseismology (He depends on EOS) • Sound speed – Precision 10-4 YCZ(0.248)  10 % < Y0(0.27) Diffusion

  33. Ys=0.243 Rcz/R=0.727 Ys=0.246 Rcz/R=0.714 Trouble in Paradise ... The Paradise ... with new abundances Rcz/R = 0.713 ± 0.001 Ys = 0.248 ± 0.003 … with the oldabundances …

  34. The terrible tragedy of Science is the murder of beautiful theories (SSM)by ugly facts(new solar abundances).W. Fowler *The mostinterestingtopicsare the oneswhereTheory and Observations disagree. *Thanks to these challenges Progressis made in bothfields

  35. However… two recent values of Z in the CZ… in agreement with the low solar Z! * Z=0.0142 (Houdek & Gough (2011) * Z from 0.008 to 0.013 (Vorontsov et al. 2012) ?

  36. After the solar neutrino debate for more than 30 years are we going to live another « long » debate with the solar composition? (Marc Pinsonneault) * The SSM has been the winner vs solar neutrinos after more than 30 years of debate * The debate « Solar abundances vs SSM » is only less than 10 years old!!! Winner?

  37. M. Asplund P. Scott N. Grevesse J. Sauval

  38. HOT NEWS … FUTURE … 3D modelswithmagneticfield (Fabbian,…,Nordlund, …) - impacts on abundances! ? Fe: smallincrease O:atoms, verysmallincrease?; moleculessmallincrease? But these 3D+MHD models have to beimproved to pass the tests wementioned (shapes, CLV, ….)

  39. THANK YOU

  40. Our sun last Friday night observed in the UV THANK YOU

  41. Transit of Venus June 6, 2012 seen by SWAP builtat CSL; on board a smallbelgian satellite Proba2 THANK YOU

  42. Balance 1D-3D Various ways to test models NO DOUBT about the REALISM of the 3D MODELS They OUTPERFORM all the 1D models! • Test 1D 3D • Ic=F() YesYes • C/L variation Yes Yes • Granulation No Yes • Widths of lines Yes* Yes • Shifts of lines No Yes • Asymmetries No Yes • ≠ indicators No Yes • Dependence I,EexcNo Yes • High freq oscillations No Yes * Thanks to fake parameters: micro- and macroturbulence

  43. 3D successes ! (continued) • Topology and convective motions For the first time, line profiles are perfectly reproduced • But computing time !

  44. SHAPES of the LINES • Observations : All line profiles* show … • Widths much larger than thermal widths • (with 1D models…microturbulence!!!) • centerblueshifted (2 mA ~ 100 m/s at 600 nm) • Asymmetries (C shapes : ~ 300 m/s i.e. 6 mA) * NON BLENDED LINES, of course

  45. 1-Averaged line profiles 1D vs Sun 3D vs Sun Shift! No micro- and macroturbulence needed in 3D!

  46. 2- Line asymmetries Theasymmetries and shiftsof spectral lines are very well reproduced Observations 3D model

  47. Summary C,N,O Other elements • 3D : Granulation and line profiles • NLTE when possible • All indicators agree • No dependence on I or Eexc …but some increase! (see next slide a comparison New-Old with AG(Grevesse and Anders,1989) ans GS(Grevesse and Sauval,1998)

  48. Metallicity Z

  49. Protosolar X, Y, Z

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