Neon , Opacity the Universe and Everything

1. Neon , Opacity the Universe and Everything • 2004: The “solar model problem” • 2005: Neon in late-type stars • 2006: • What solar model problem? • What is the real solar neon abundance? • The Universe and Everything Jeremy Drake Smithsonian Astrophysical Observatory

3. c.2003 new solar photospheric abundance analyses using 3-D hydrodynamic atmosphere models found C, N and O abundances lower by 25-30% (Asplund et al 2004)

4. G.W. Bush takes office The rise and fall of the solar oxygen abundance(Ayres et al 2006) • “At recent rate of decline, the Sun will run out of oxygen in about 2015”

5. 2004: Solar Model Breaks!

6. Badnell et al (2005) OP-OPAL opacities Standard solar model The Solar Model Problem • Models calculated with Asplund et al (2004) abundances fail to predict sound speed, He abundance and depth of convection zone inferred from helioseismology (Bahcall et al 2005; Antia & Basu 2005) • Opacity problem but appears beyond uncertainties in current atomic data (Seaton & Badnell 2004; Badnall et al. 2005; Bahcall et al. 2005) Antia & Basu 2004, Bahcall et al 2005: Might be fixed IF solar Ne is ~2.5x higher Bahcall et al (2005)

7. But cosmic Neon abundance known for 50 years… Aller (1957) Ne/O=0.15

8. …in nebulae and the solar corona… Pottasch (1963) Pottasch (1963) Ne/O=0.12

9. It’s… Acton et al (1976) • Average of 25 different measurements of OVIII/Ne IX X-ray fluxes ==> N(O)/N(Ne)=0.21+/- 0.07 Ne/O=0.21

10. …always… Meyer (1985) Ne/O=0.14

11. …seemed… Grevesse, Noels & Sauval (1996) Ne/O=0.16 (note log10+12 scale)

12. …to be.. Ne/O=0.14 Widing (1998): Newly-emerged active regions

13. …about Ne/O=0.16 Henry (1998): HII regions in MW and spiral galaxies

14. Pre-flight simulation Chandra, XMM: Coronal abundances - a Neon Surprise • The first spectra from Chandra revealed remarkably strong Ne X lines Ne X Fe XVII O VIII Ne IX

15. Ne/O Ratios from Coronal Spectra (Drake & Testa 2005) • UseT-insensitive ratio constructed from O VIII, Ne IX and Ne X • Integration over test DEM(T) --> systematic errors ~<0.1 dex

16. Ne/O Ratios in Stars of the Local Cosmos • Ne/O remarkably constant and 2.7 times higher than Asplund et al (2004) - just right to fix the solar model! Ne/O=0.42 Drake & Testa (2005)

17. Just a FIP Effect? HR1099 vs Sun Sun Brinkman et al (2001)

18. Guedel (2004) Fe fractionation in stellar coronae

19. Ne/O Ratios in Stars of the Local Cosmos • Ne/O remarkably constant and 2.7 times higher than Asplund et al (2004) - just right to fix the solar model! Drake & Testa (2005)

20. Objection! • Quiet sun CDS EUV Ne IV-VI, O III-V: “…the photospheric abundance of neon is not responsible for the discrepancies between standard solar models and helioseismological observations” - Young (2005) • Re-analysis of old solar SMM X-ray Ne IX, O VIII: "...the enhanced-neon hypothesis will not resolve the current controversy" - Schmelz et al (2005)

21. Dead Horse • Solar + local cosmic abundance: "The evidence is thus stacked against the solar Ne/O ratio being as high as 0.4 ... the solar model problem still awaits a solution.” - Asplund et al, astro-ph/0510377 • Delahaye & Pinnsoneault (2006):“…models constructed with low oxygen and high neon are inconsistent with the solar sound speed profile”

22. Ayres et al (2006) What Solar Model Problem? • Re-analysis and review of solar CNO abundances and non-LTE corrections: “we obtain intermediate abundances…the errors are too large to conclude there is a solar abundance problem” - Pinsonneault & Delahaye (2006) • Fine analysis of IR CO bands giving O/H=8.85: “…our conclusions do not support such a revision [of the O abundance]” - Ayres et al (2006)

23. McKenzie & Feldman (1992) What is the real solar Ne abundance? P78 SOLEX Ne/O=0.08 Ne/O=0.2

24. Ne Fractionation in Solar Corona (Drake 2006) Based on P78 fluxes (McKenzie & Feldman 1992) • Which, if any, solar coronal measurements represent underlying Sun? • Rising Ne/O vs T reminiscent of higher values in more active stars Solar Ne/O depends on plasma T

25. The Universe and Everything “The typically derived Ne/O ratios in hot stars, H II regions and planetary nebulae are in very good agreement with our advocated solar value” - Asplund et al (2005 astro-ph/0510377)

26. Current Evidence for “standard” Ne/O • Ne/O=0.19,0.2 X-ray ISM absorption measurements using X-ray binaries (Juett et al 2006, Yangsen & Wang 2006) • Ne/O~0.15 most(?) c1990-2000 H II region studies (eg Henry 1998; (but ORL vs CEL issue?!))

27. Ne/O=0.4 Ne/O=0.15 Drake (2006) Evidence for higher Ne/O • Ne/O=0.4 Heliopause, local ism pickup ions (Frisch & Slavin 2004, Gloeckler & Geiss 2004) • Ne/O=0.4 ISM toward Crab (Pollock et al. 2005) • Ne/O~>0.5 IGM (Nicastro et al 2005) • Ne/O=0.3-0.5 B stars, BA supergiants (Sigut 1999,Killian et al 1994, Przybilla et al 2005, Cunha et al 2006) • Ne/O=0.3 PNe (Liu et al 2003, Perinoto et al 2004, Stranghellini et al 2006)

28. Supernova Yield Problems? Woosley & Weaver (1995) Samland (1998) Nomoto et al (1997) Henry (1998): HII regions in MW and spiral galaxies

29. Conclusion • Many cosmic sources now indicate Ne/O about x2 higher than the currently favoured solar ratio of Ne/O=0.15 • The solar outer atmosphere indicates significant fractionation of Ne content is at work. Ne/O is plausibly depleted in the corona and the true solar Ne abundance about x2 higher. • The answer is still important for the solar model, supernova metal production and the metal content and evolution of the universe.