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Big Bang Nucleosynthesis: Theory vs. Observation

Big Bang Nucleosynthesis: Theory vs. Observation. TASI 2009 Michael S. Turner 4 June 2009. 0.07 MeV. 0.2 MeV. 0.01 MeV. 1 MeV. D leads. 10 MeV. NSE, n/p~1/6. Thermal Equilibrium. BBN. BBN Reaction Network: the big 12. He-4 Prediction (95%): n ↔ p

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Big Bang Nucleosynthesis: Theory vs. Observation

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  1. Big Bang Nucleosynthesis: Theory vs. Observation TASI 2009 Michael S. Turner 4 June 2009 Michael S Turner

  2. Michael S Turner

  3. Michael S Turner

  4. 0.07 MeV 0.2 MeV 0.01 MeV 1 MeV D leads 10 MeV NSE, n/p~1/6 Thermal Equilibrium BBN Michael S Turner

  5. BBN Reaction Network: the big 12 Michael S Turner

  6. He-4 Prediction (95%): n ↔ p ΔY = ±0.0004 (τn) ±0.0004 (th) -0.002? ΔY = ±0.0002 Δτn/sec τ(n) = 885.7 ± 0.8 sec (±0.1%) …but, Serebrov (2005): 878.5 ± 0.8 sec (-0.8% or -6.5 σ)??##!! Michael S Turner

  7. D/H Prediction (95%): ±8% d(d,n)He-3 and d(p,γ)He-3 Michael S Turner

  8. Li-7 Prediction (95%): ±25% p(n,γ)d, He-3(α,γ)Be-7, d(p,γ)He-3, d(d,n)He-3 Michael S Turner

  9. Reaction Cross Sections are measured where they are needed – no need to extrapolate. Sharp contrast to stellar models Michael S Turner

  10. BBN Predictions • (95% cl) • Deuterium: baryometer! • He-4: go/no-go test of big bang • Li-7: consistency test; • stellar probe? • He-3: probe of chemical evolution Michael S Turner

  11. Light Element AbundancesD, He-4 and Li-7 • Deuterium: stars only destroy D – need pristine samples of the Universe • He-4: MS stars make He-4 – need old, metal poor stars • Li-7: also made by cosmic rays, destroyed by stars, • He-3: made and destroyed by stars, learn more about chemical evolution! Michael S Turner

  12. Michael S Turner

  13. Burles/Tytler, ApJ 499, 699 (1998) Detecting Deuterium Michael S Turner

  14. O’Meara et al: 6 Deuterium Systems D/H = 2.8 ± 0.3 x 10-5 • BBN (Deuterium) • Ωbh2 = 0.0213 ± 0.0013 (D) ± 0.0004 (th) • YP = 0.248 ± 0.005 (D) ± 0.0002 (th) ± 0.0002 (τn)  Li-7/H = 4.3 ± 0.5 x 10-10 -0.002? Michael S Turner

  15. Precision Cosmology Indeed! CMB (first to second peak) Ωbh2 = 0.0225 ± 0.0006 vs. BBN (Deuterium) Ωbh2 = 0.0213 ± 0.0013 ~5% agreement Ωb = 0.044 ± 0.002 h = H0/100 km/s/Mpc ~ 0.7 Michael S Turner

  16. He-4: 0.24x, Struggling for the 3rd Sig Fig YP = 0.248 ± 0.005 (D) ± 0.0004 (th) ± 0.0004 (τn) -0.002? Michael S Turner

  17. He-4: 0.24x, Struggling for the 3rd Sig Fig YP = 0.248 ± 0.005 (D) ± 0.0004 (th) ± 0.0004 (τn) -0.002? • Biggest issue: control of systematic error (see Peimbert, arXiv: 0811.2980) • State of the art, based upon extragalactic HII regions, Peimbert et al, ApJ 666, 636 (2007): YP = 0.2477 ± 0.003 • Concordance with D/BBN prediction Michael S Turner

  18. Li-7: Not as simple as once thought Li-7/H (D/H) = 4.3 ± 0.5 x 10-10 • Spite plateau: Li-7/H = 1.3 ± 0.3 x 10-10 • Factor of 3 discrepancy (for ~10 years)! • Possible explanation: Korn et al, Nature 442, 657 (2006): astration by gravitational settling • Inferred value by Korn et al : (3.5 ± 0.8) x 10-10 Michael S Turner

  19. Selected BBN References • Recent reviews • Schramm/Turner, RMP 70, 303 (1998) • Steigman, ARNPS 57, 463 (2007) • Predicted abundances and uncertainties • Nollett/Burles, PRD 61, 123505 (2000) • Burles/Nollett/Turner, ApJ 552, L1 (2001) • Lopez/Turner, PRD 59, 103502 (1999) • Cyburt, PRD 70, 023505 (2004) • Serpico, JCAP 0412 (2004) 010 • Serebrov et al, PLB 605, 72 (2005) • Deuterium • O’Meara et al, ApJ 649, L61 (2006) Michael S Turner

  20. CMB anisotropy is a non-trivial map of density inhomogeneity to temperature fluctuations: Mapping depends upon cosmological parameters (good news!) ΩMh2 Michael S Turner

  21. γ/neutrinos Quark/Hadron All SM Particles e± pairs Relativistic Degrees of Freedom Michael S Turner

  22. Neutrino Counting • BBN (pre-LEP): Nν< 4 • Lab (LEP): Nν= 2.994 ± 0.012 • BBN: Nν< 3.2 (95%) • CMB: Nν = 4.4 ± 1.5 Michael S Turner

  23. BBN: GR Independent Quenched ReactorCarroll/Kaplinghat, PRD 65, 063507 (2002) Michael S Turner

  24. “Precision Cosmology”with SDSS + WMAP: concordance model Standard Hot Big Bang of the 1970s Flat, accelerating Universe Atoms, exotic dark matter & dark energy Consistent with inflation Precision set of cosmological parameters Ω0 = 1.005 ± 0.006 (uncurved) ΩM = 0.28 ± 0.013 ΩB = 0.045 ± 0.002 ΩΛ = 0.72 ± 0.02 H0 = 70 ± 1.3 km/s/Mpc t0 = 13.73 ± 0.12 Gyr Nν = 4.4 ± 1.5 Consistent with all data, laboratory and cosmological! Michael S Turner

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