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(Primordial Nucleosynthesis*) B. Kämpfer Research Center Rossendorf/Dresden & Technical University Dresden - Expanding Universe - Prior to Nucleosynthesis - First Three Minutes: Creating Light Nuclei * Based on Ms. of W. Wustmann, July 22, 2005 BBN
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Albert Einstein, 14.03.1879-18.04.1955 1905: - Über einen die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen Gesichtspunkt - Die von der molekularkinetischen Theorie der Wärme geforderten Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen - Elektrodynamik bewegter Körper - Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig? 1915:
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Framework/Propositions 1. Einstein Equations Hold for Universe 2. Cosmological Principle Homogeneity & Isotropy of 3D 4. --> Friedmann Equations 3. Iso-entropic Expansion
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Expanding Universe larger e,p faster cooling: Issues: Nucleosynthesis: test of expansion dynamics CMB: 300,000 years, Now:
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Prior to Nucleosynthesis 1. Confinement: Hadrosynthesis BK, Bluhm, 2005
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2. Strongly Interacting Matter quarks gluons confinement
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temperature evolution strangeness evolution strangeness changing weak interactions
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3. Radiation Universe
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Stretching of Distances T = 170 MeV 5 m1 fm100000 fm1 fm q q g 1000 fm q T = 2.3 x 10 MeV -10 On averageOn Earth In nuclei & neutron stars BBB
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The Universe as Reactor Friedmann: T(t) from D: baryometer 4He: chronometer only destruction after BNN
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Primordial Nuclear Network 2. D, 4. 3He, 8. T, 6. 4He, 7. 7Li Dominant Channels (strong int./QCD): T < 1 MeV: e+ e- annihilation (QED) nu decoupling (e.w. int.)
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p n DT He Be Li 1 2 5 6 3 4 8 9 10 12 11 7 7 7 34 Nollett-Burles
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Rate Equations for 2 2 Processes rates (T) Init. Conds.: earlier equilibrium values add decays integrate up to freeze-out done T(t)
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Survey on Data Nollett-Burles 2000
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freeze-in all other parameters and consider only the impact of this reaction poor data samples:
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Evolution of Abundances D Be mass fraction
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Cosmic Concordance? new physics beyond Standard Model? Xdimensions, more neutrinos, axions, SUSY particles, G(t),...
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WMAP: Precision Cosmology time BBN
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Knowing only Photo Dissociation Data Bishop 50 Shinohara 49 de Graeve 92 Role of n(p,D)gamma
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Knowing more Data detailed balance: S n p D
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error bars suppressed EFT: the tool of strong interaction at low energies adjusted to Cox 65 low energy: high energy: N isovector mag. moment Low Energy Data np D gamma Bethe 49
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data too scarce for precision cosmology new measurements at ELBE Grosse, Beyer & Co „GamoW window“
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FZ Rossendorf ELBE Bremsstrahlung cave: p n D 1. D at rest: T_p, T_n 2. Superposition of various beam energies thermal spectrum A. Wagner
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FZ Rossendorf ELBE nTOF cave n p D pulsed n source: A. Junghans J. Klug
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Previous Measurements Suzuki et al. 95: Hara et al. 03: Moreh et al. 89: Nagai et al. 97: Cokinos, Melkonian 77: other exps.: M1 vs. E1
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Xsection R factor Rate ENDF
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Using Rates in BBN123 5% lowering of 7Li (relative to SKM&EFT)
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Sensitivity Function measure here!
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Neutron Life Time nearly all n are in 4He: Y(4He) depends on (other abundances are robust) and also on fastBBN 886.7 869 904
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Number of Light Neutrinos 3 3.5 2.5
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Conclusions more data for gamma D n p at E_gamma <,= 2.32 MeV: pin down primordial 7Li abundance below a 5% level more precise data for other reactions & more precise observational data: NEW PHYSICS? BBN vs. CMB
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Deviations of Data and SKM(5): R Factor 13%
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WMAP 885.7 sec 878.5 sec Mathews,Kajino,Shima 05 Steigman 05 9 orders of magnitude BBN with eta(WMAP) Helium-4 mass fraction eta from BBN adjusted to obs. Metal-poor Extragalactic H II regions
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Deuteron Abundance: Observations BBN with eta_10=6.1 X = metallicity (O,Si)
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Impact of Changed Xsections 10% change of rate
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