1. The Solar Chemical Composition Nicolas Grevesse
Centre Spatial de Liège and Institut d´Astrophysique et de Géophysique, Université de Liège, Belgium
Padova- November 21, 2007

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

3. HOW ? Photospheric spectrum - vis.+IR - absorption lines - neutral
and once ionized (T:5000K) + few molecules i j
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
Padova- November 21, 2007 3

4. Solar O,C  HT TPICS  Solar Fe? Solar Neon?
Padova- November 21, 2007

5. Solar Metallicity, Z O+C=61% of Z O+C+Fe+Ne=80% of Z
Element
Abundance
Contribution to Z (%) O
8.69
42.9 C
8.43
17.7 Fe
7.50
9.7 Ne
7.93
9.4 Mg
7.60
5.3 N
7.83
5.2 Si
7.51
5.0 S
7.12
2.3
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= Y= Z= Z/X=0.0181
Padova- November 21, 2007

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

7. New Solar Chemical 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 COMPREHENSIVE and HOMOGENEOUS re-determination of the abundances of nearly all the elements in the sun.
Such an analysis had not been done since many decades!!

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
available elements
BASIC INGREDIENTS
New 3D model instead of the classical 1D models of the
lower solar atmosphere
Careful and very demanding selection of the spectral
lines… AVOID blends!!! NOT TRIVIAL!!!
Permanent CONCERN: QUALITY rather than QUANTITY
Careful choice of the atomic and molecular data
NOT TRIVIAL!!!!
NLTE instead of the classical LTE hypothesis…
WHEN POSSIBLE !!!
Use of ALL indicators (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).
Padova- November 21, 2007

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

15. Conclusions: Forbidden lines better than OH lines
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 ~ to 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 blend with Ni I line (37%)
blend with two CN lines (31%)
blend with C2 and CN lines (63%)
We estimated the contributions of the blends independently of any model, in a purely empirical way, from observations of other lines 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: dex
3D-1D model: 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. Why has the abundance of O decreased?
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?
In the nineties, with 1D HM Model…(NG,JS,AN)
(AG89, GN93, GS98)
Forbidden lines - no blends - ~
Permitted lines - LTE - ~
Molecular lines – T too large - ~
Good agreement: High O
Today…(AGSS09)
Forbidden lines – Blends ! O down to 8.70 (model 3D - 1D ~ 0)
Permitted lines – NLTE ! O down to (model 3D - 1D ~ 0)
Molecular lines – Model ! O down to 8.69
GOOD AGREEMENT: LOW O

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
Lines
Holweger-Müller(1D) 3D
3D-HM
[O I]
8.73+/-0.05
8.70+/-0.05
-0.03
O I
8.69+/-0.05
0.00
OH, dv=0
8.83+/-0.03
8.69+/-0.03
-0.14
OH, dv=1
8.86+/-0.03
-0.17
If LTE (O I): log O=8.82+/ [mean Δ(NLTE)=-0.13 dex] !!!
Δ(NLTE) depends strongly on collisions with H atoms
Padova- November 21, 2007

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
Lines
Holweger-Müller
AGSS09
3D-HM
[C I]
8.41
0.00
C I
8.45+/-0.04
8.42+/-0.05
-0.03
CH, dv=1
8.53+/-0.04
8.44+/-0.04
-0.09
CH, A-X
8.51+/-0.03
8.43+/-0.03
-0.08
C2, Swan
8.46+/-0.03
-0.05
CO,dv=1
8.60+/-0.01
8.44+/-0.01
-0.16
CO,dv=2
8.69+/-0.02
-0.25
Padova- November 21, 2007

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
Element
Grevesse & Noels (1993)
AGSS
(2009)
Difference
Carbon
8.55+/-0.05
8.43+/-0.05
-0.12 dex
Nitrogen
7.97+/-0.07
7.83+/-0.05
-0.14 dex
Oxygen
8.87+/-0.07
8.69+/-0.05
-0.18 dex
Forget about Anders-Grevesse 89, GN93, Grevesse-Sauval 98
USE AGSS09!
Padova- November 21, 2007

24. Solar Ne abundance … Ne/O
We used Ne/O=0.175  (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
Padova- November 21, 2007

25. Solar Ne abundance
New analyzes of solar neighborhood suggested that solar Ne is underestimated (Ne/O=0.3 to 0.4)
Ne/O
X-ray luminosity
Drake&Testa(2005)*
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. Solar Ne abundance
Recent studies of solar neighborhood show that solar Ne is NOT underestimated !
Robrade, Schmitt & Favata (2008)
Ne/O
X-ray luminosity
Drake & Testa (2005):
(see also Liefke and Schmitt (2006))

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

28. (Some) Implications
Padova- November 21, 2007

29. New solar metallicity O+C=61% of Z O+C+Fe+Ne=80% of Z
Element
Abundance
Contribution to Z (%) O
8.69
42.9 C
8.43
17.7 Fe
7.50
9.7 Ne
7.93
9.4 Mg
7.60
5.3 N
7.83
5.2 Si
7.51
5.0 S
7.12
2.3
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= Y= Z= Z/X=0.0181
Anders, Grevesse Z= Z/X=0.027
Grevesse, Noels Z= Z/X=0.024
Grevesse, Sauval Z= Z/X=0.023
NOTE: Uncertainty on Z: 12%... Z from to
By number H  91.3%, He  8.5%,  other elements  0.15%
Padova- November 21, 2007

30. Synergies between solar and stellar modeling, Rome, 22-26 June 2009
Mean difference Sun - Meteorites  0.05
Synergies between solar and stellar modeling, Rome, June 2009
NIC IX, June 2006
Padova - November 21, 2007

31. a grain of sand But … in the honeymoon between SSM-Helioseismology
Padova- November 21, 2007

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

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

34. The terrible tragedy of Science is the murder of
beautiful theories (SSM) by ugly facts (new solar
abundances) W. Fowler
*The most interesting topics are the ones where Theory and Observations disagree.
*Thanks to these challenges Progress is made in both fields

35. ? However… two recent values of Z in the CZ…
in agreement with the low solar Z!
* Z= (Houdek & Gough (2011)
* Z from to (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 models with magnetic field
(Fabbian,…,Nordlund, …) - impacts on abundances! ?
Fe: small increase
O: atoms, very small increase?; molecules small increase?
But these 3D+MHD models have to be improved to pass the
tests we mentioned (shapes, CLV, ….)

39. THANK YOU
Padova- November 21, 2007

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

41. THANK YOU Transit of Venus June 6, 2012 seen by SWAP built at CSL; on
board a small belgian 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() Yes Yes
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,Eexc No 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!!!)
center blueshifted (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!
Padova- November 21, 2007

46. The asymmetries and shifts of spectral lines are very well reproduced
2- Line asymmetries
The asymmetries and shifts of spectral lines are very well reproduced
Observations
3D model
Padova- November 21, 2007

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

49. Metallicity Z

50. Protosolar
X, Y, Z

51. (but don’t use them anymore!!! USE….see next slide!!
20 years ago: Grevesse-Noels(1993)
(also Anders-Grevesse 89, Grevesse-Sauval 98)
High O, C, … High Z
THANKS for TRUSTING our data
(but don’t use them anymore!!!
USE….see next slide!!

52. Theoretical Solar Cycle (its many elements)
EMERGING
LOOP
PHOTOSPHERE
LOCAL
DYNAMO
ROTATION
CONVECTION
ZONE
MAGNETIC
PUMPING
MAGNETIC
BUOYANCY
GLOBAL
DYNAMO
TACHOCLINE
RADIATIVE
INTERIOR