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The influence of (some) nuclear reaction rates

INAF. The influence of (some) nuclear reaction rates on the evolution of the stars of low, intermediate and high mass. Alessandro Chieffi Istituto Nazionale di AstroFisica (Istituto di Astrofisica Spaziale e Fisica Cosmica) &

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The influence of (some) nuclear reaction rates

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  1. INAF The influence of (some) nuclear reaction rates on the evolution of the stars of low, intermediate and high mass Alessandro Chieffi Istituto Nazionale di AstroFisica (Istituto di Astrofisica Spaziale e Fisica Cosmica) & Centre for Stellar and Planetary Astrophysics – Monash University - Australia Email: alessandro.chieffi@iasf-roma.inaf.it In collaboration with Marco Limongi

  2. 25 MO 5 MO 1 MO

  3. SOLAR DISTRIBUTION

  4. OUTLINE The 14N(p,g) and the age of the Galactic Globular Clusters The influence of the 3a and the 14N(p,g) on the AGB evolution The 25Mg(p,g) and the abundance of the 26Al in the wind of the WR stars The 12C12C and the odd-even effect The 12C(a,g) and the advanced burning phases

  5. The 14N(p,g) cross section and the age of the Galactic Globular Clusters HB RGB TO MS

  6. The 14N(p,g) cross section and the age of the Galactic Globular Clusters Basic steps necessary to determine the age of a cluster: 1) Determine the theoretical t=f(LTO,c.c.) HB RGB TO MS 3) Enter the LTO(GC) in the theoretical t=f(LTO,c.c.) and the game is over!

  7. The 14N(p,g) cross section and the age of the Galactic Globular Clusters Basic steps necessary to determine the age of a cluster: f(LTO,c.c.,14N(p,g)) 1) Determine the theoretical t=f(LTO,c.c.) HB 2) Determine the distance of the cluster in order to find LTO(GC) RGB LHB(14N(p,g)) MS fitting method HB Luminosity method HB theoretical TO Reference MS distance MS distance HB G.C. G.C. MS 3) Enter the LTO(GC) in the theoretical t=f(LTO,c.c.) and the game is over!

  8. Z=10-4 Y=0.23 Solid => reference Dashed => (14N(p,g)15O) / 2 10 Gyr 13 Gyr The TO clock gives larger ages because the CNO cycle is less efficient Current age determinations raised by roughly 1 Gyr or little less

  9. The 14N(p,g) cross section and the age of the Galactic Globular Clusters Basic steps necessary to determine the age of a cluster: f(LTO,c.c.,14N(p,g)) 1) Determine the theoretical t=f(LTO,c.c.) HB 2) Determine the distance of the cluster in order to find LTO(GC) RGB LHB(14N(p,g)) MS fitting method HB Luminosity method HB theoretical TO Reference MS distance MS distance HB G.C. G.C. MS 3) Enter the LTO(GC) in the theoretical t=f(LTO,c.c.) and the game is over!

  10. RGB phase H-rich mantle H burning shell He core T Compressional heating n losses and electron degeneracy T 3 a ignition T CNO efficiency He core mass

  11. The 14N(p,g) cross section and the age of the Galactic Globular Clusters Basic steps necessary to determine the age of a cluster: f(LTO,c.c.,14N(p,g)) 1) Determine the theoretical t=f(LTO,c.c.) HB 2) Determine the distance of the cluster in order to find LTO(GC) RGB LHB(14N(p,g)) MS fitting method HB Luminosity method HB theoretical TO Reference MS distance MS distance HB G.C. G.C. MS 3) Enter the LTO(GC) in the theoretical t=f(LTO,c.c.) and the game is over!

  12. M=0.8 MO Y=0.23 Z=10-4 Red – reference Blue – 14N(p,g)15O / 2 • MHe = 1% • Mbol(tip) = 0.055 Mag 0.15 Mag => - 2 Gyr

  13. The 14N(p,g) cross section and the age of the Galactic Globular Clusters Basic steps necessary to determine the age of a cluster: f(LTO,c.c.,14N(p,g)) 1) Determine the theoretical t=f(LTO,c.c.) HB 2) Determine the distance of the cluster in order to find LTO(GC) RGB LHB(14N(p,g)) MS fitting method HB Luminosity method HB theoretical TO Reference MS distance MS distance LTO(GC) increases HB G.C. G.C. MS 3) Enter the LTO(GC) in the theoretical t=f(LTO,c.c.) and the game is over!

  14. age 14N(p,g) LUNA 14N(p,g) NACRE MS fitting HB fitting LTO(GC)

  15. He burning shell H-rich mantle H burning shell CO core R(Hshell) ~10-5 Rstar Neutron production s process nucleosynthesis AGB phase: 0.7 < M / MO < 7 He luminosity

  16. He burning shell H-rich mantle H burning shell CO core R(Hshell) ~10-5 Rstar Convective envelope Neutron production s process nucleosynthesis H shell M(MO) He shell t(yr) AGB phase: 0.7 < M / MO < 7

  17. He burning shell H-rich mantle H burning shell CO core R(Hshell) ~10-5 Rstar Neutron production s process nucleosynthesis AGB phase: 0.7 < M / MO < 7 Convective envelope H shell M(MO) He conv. shell He shell t(yr)

  18. AGB phase: 0.7 < M / MO < 7 M=3 MO - Z=0.02 Reference 3a / 2 3a x 2 14Npg / 5

  19. AGB phase: 0.7 < M / MO < 7 SURFACE CARBON ABUNDANCE Reference 3a / 2 3a x 2 14Npg / 5

  20. 26Al production in central H burning 28Si 29Si 26Al 27Al P The 25Mg is the initial one (usually scaled solar) 24Mg 25Mg 26Mg N 26Al profile at central H-exhaustion Central concentration versus time

  21. 26Al production in central H burning

  22. The 12C12C rates and the odd-even effect

  23. The 12C12C rates and the odd-even effect

  24. 35Cl 37Cl 32S 33S 34S 36S 31P 28Si 29Si 30Si 27Al 24Mg 25Mg 26Mg P 23Na 20Ne 21Ne 22Ne 19F 16O 17O 18O 14N 15N 12C 13C N

  25. 35Cl 37Cl 32S 33S 34S 36S 31P 28Si 29Si 30Si 27Al 24Mg 25Mg 26Mg P 23Na 20Ne 21Ne 22Ne 19F 16O 17O 18O 14N 15N 12C 13C N

  26. The King rate: 12C(a,g)16O Stars more massive than 0.5 MO burn He in a convective core! a a 16O 12C a a

  27. The King rate: 12C(a,g)16O

  28. The King rate: 12C(a,g)16O

  29. The King rate: 12C(a,g)16O

  30. CONCLUSIONS Why the background is green? Because the green color is synonymous of hope... ... and the hope is to have an improved set of cross sections shortly!

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