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The Universe is expanding

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  1. The Universe is expanding • The Universe is filled with radiation • The Early Universe was Hot & Dense • The Early Universe was a Cosmic Nuclear Reactor!

  2. ~ 100 s after the Big Bang Primordial Nucleosynthesis ~ 1 - 10 Gyr LSS ~ 0.1 s after the Big Bang Neutrinos Decouple ~ 400 kyr after the Big Bang Relic Photons (CMB) are free

  3. Neutron Abundance vs. Time / Temperature p + en + e … Rates set byn “Freeze – Out” ? Wrong! (n/p)eq BBN “Begins”  Decay

  4. nmeasurements vs. time Statistical Errors versus SystematicErrors! 885.7  0.8 sec

  5. BBN “Begins” at T  70 keV when n / p  1 / 7 Coulomb Barriers and absence of free neutrons terminate BBN at T  30 keV tBBN  4  24 min.

  6. Pre - BBN Post - BBN Only n & p Mainly H & 4He

  7. Baryon Density Parameter   nN /n ; 10    = 274 Bh2 where : B  B /c and : h  H0 /100 km/s/Mpc  0.7 Note : Baryons  Nucleons

  8. Evolution of mass - 2 10 More nucleons  less D

  9. Two pathways to mass - 3 More nucleons  less mass - 3

  10. Two pathways to mass - 7

  11. BBN abundances of masses – 6, 9 –11 Abundances Are Very Small !

  12. BBN – Predicted Primordial Abundances BBN Abundances of D, 3He, 7Li are RATE (Density) LIMITED 7Li 7Be D, 3He, 7Li are potential BARYOMETERS

  13. Use BBN (D/H) P vs. 10to constrain B Predict (D/H)P “Measure” (D/H) P Infer B (B) at 20 Min.

  14. Y is very weakly dependent on the nucleon abundance All/most neutrons are incorporated in 4He n/p  1/7  Y  0.25 Y4He Mass Fraction Y 4y/(1 + 4y) y  n(He)/n(H) YP DOES depend on the competition between Γwk & H

  15. 4He (mass fraction Y) is NOT Rate Limited • 4He IS n/p Limited Y is sensitive to the EXPANSION RATE ( H 1/2 ) • Expansion Rate Parameter : S  H´/H • S  H´/H  (´/)1/2 (1 + 7N /43)1/2 • where ´   + N andN  3 + N

  16. The Expansion Rate (H  Hubble Parameter) Is A Probe Of Non-Standard Physics • S2  (H/ H)2= G/G  1 + 7N /43 • * S can be parameterized by N N (-) /  and N  3 + N NOTE : G/ G = S2 1 + 7N / 43 • 4He is sensitive to S (N) ; D probes B

  17. 4Heis an early – Universe Chronometer Y vs. D/H N =2, 3, 4 (S = 0.91, 1.00, 1.08) Y0.013N 0.16 (S – 1)

  18. Isoabundance Contours for 105(D/H)P & YP YP & yD  105 (D/H) 4.0 2.0 3.0 0.25 0.24 0.23 D&4HeIsoabundance Contours Kneller & Steigman (2004)

  19. Kneller & Steigman (2004) & Steigman (2007) yDP 105(D/H)P = 46.5 (1 ± 0.03) D-1.6 YP = (0.2386 ±0.0006) + He / 625 y7  1010(7Li/H) = (1.0 ± 0.1) (LI)2 / 8.5 where : D 10 – 6 (S – 1) He  10 – 100 (S – 1) Li  10 – 3 (S – 1)

  20. Post – BBN Evolution • As gas cycles through stars,D is only DESTROYED • As gas cycles through stars,3He is DESTROYED , • PRODUCED and, some 3He SURVIVES • Stars burn H to 4He (and produce heavy elements) •  4He INCREASES (along with CNO) • Cosmic Rays and SOME Stars PRODUCE 7Li BUT, • 7Li is DESTROYED in most stars

  21. Observing D in QSOALS Ly -  Absorption

  22. Towards Primordial Deuterium Observations of Deuterium In 7 High-Redshift, Low-Metallicity QSO Absorption Line Systems 105(D/H)P = 2.7 ± 0.2 (Weighted Mean of D/H) (Weighted mean of log (D/H) 105(D/H)P = 2.8 ± 0.2)

  23. (D/H)obs + BBNpred10 =6.0± 0.3 BBN V. Simha & G. S.

  24. CMB Temperature Anisotropy Spectrum (T2 vs. ) Depends On The Baryon Density  10=4.5,6.1,7.5 V. Simha & G. S. The CMB provides an early - Universe Baryometer

  25. CMB + LSS10 =6.1±0.2 10Likelihood CMB V. Simha & G. S.

  26. Primordial Deuterium Predicted BBN + CMB/LSS  105(D/H)P = 2.6 ± 0.1

  27. BBN (~ 20 min) & CMB (~ 380 kyr) AGREE 10Likelihoods CMB BBN V. Simha & G. S.

  28. Oxygen Gradient In The Galaxy

  29. 3He Measured In Galactic HII Regions SBBN

  30. 3He Measured In Galactic HII Regions SBBN

  31. 4He Observed In Extragalactic H  Regions As O/H  0, Y  0 SBBN Prediction : YP = 0.248 K. Olive YP = 0.240 ± 0.006 ( Or : YP < 0.255 @ 2 σ )

  32. SBBN 10Likelihoods from D and 4He AGREE ? to be continued …

  33. But ! Lithium – 7 Is (ALSO) A Problem [Li] ≡ 12 + log(Li/H) [Li]SBBN 2.6 – 2.7 [Li]OBS 2.1 Li too low !

  34. Baryon Density Determinations: Consistent ? Late - Decaying NLSP ? ? N< 3 ? Observational Uncertainties Or New Physics?

  35. YP vs. (D/H)P for N = 2, 3, 4 N  3 ?

  36. A Non-Standard BBN Example (Neff < 3) Late Decay of a Massive Particle Kawasaki,Kohri&Sugiyama & Low Reheat Temp. (TR  MeV) Neff<3  Relic Neutrinos Not Fully (Re)Populated

  37. Isoabundance Contours for 105(D/H)P & YP YP & yD  105 (D/H) 4.0 3.0 2.0 0.25 0.24 0.23 Kneller & Steigman (2004)

  38. Nvs.10 From BBN (D & 4He) ( YP < 0.255 @ 2 σ ) BBN Constrains N N < 4 N> 1 V. Simha & G. S.

  39. CMB Temperature Anisotropy Spectrum Depends on the Radiation Density R(SorN)   N =1, 3,5 V. Simha & G. S. The CMB / LSS is an early - Universe Chronometer

  40. N Is Degenerate With mh2 The degeneracy can be broken - partially - by H0 (HST) and LSS 1 + zeq =m / R 1 + zeq≈ 3200 V. Simha & G. S.

  41. CMB + LSS + HST Prior on H0 Nvs.10 CMB + LSS Constrain 10 V. Simha & G. S.

  42. Use the CMB + LSS to boundη10and N Use BBN to predict YP , yDP , yLiP (solid black) Compare to the observed abundances (dashed) Korn et al. 4He D 7Li  ?  V. Simha & G. S.

  43. Even for N  3 Y + DH LiH 4.0  0.7 x 1010 yLi  1010 (Li/H) 4.0 3.0 2.0 0.25 4.0 0.24 0.23 Li depleted/diluted in Pop  stars ? Kneller & Steigman (2004)

  44. Alternative to N  3 (S  1) eDegeneracy (Non – Zero Lepton Number) YP & yD 105 (D/H) For e=e/kT  0 (more e than anti - e) n/p  exp( m/kT  e )  n/p   YP  4.0 3.0 2.0 0.23 0.24 0.25 YP probes Lepton Asymmetry D & 4HeIsoabundance Contours Kneller & Steigman (2004)

  45. Kneller & Steigman (2004) & Steigman (2007) yDP 105(D/H)P = 46.5 (1 ± 0.03) D-1.6 YP = (0.2386 ±0.0006) + He / 625 y7  1010(7Li/H) = (1.0 ± 0.1) (LI)2 / 8.5 where : D 10 + 5 e/ 4 He  10 – 574 e/ 4 Li  10 – 7 e/ 4

  46. eDegeneracy (Non – Zero Lepton Number) YP & yD  105 (D/H) For N=3 : e=0.0350.026 2.0 4.0 3.0 0.23 0.24 & 10 = 5.9  0.4  0.25 (V. Simha & G. S.)

  47. BBN Constraints (D & 4He) On eFor N = 3 e = 0.035 ± 0.026 10= 5.9 ± 0.3 V. Simha & G.S.

  48. Even With Non - Zero eDegeneracy, The 7Li Problem Persists yLi  1010 (7Li/H) [Li] = 2.6  0.7 Still ! 4.0 2.0 4.0 3.0 [Li] = 2.7  0.7 with CFO 2008 results 0.23 0.24 Li depleted/diluted in Pop  stars ? 0.25 Or, Late Decay of (Charged) NLSP ?