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Amand Faessler , Erice September 2014 With thanks to : Rastislav Hodak ,

Can we look back to the Origin of our Universe ? Cosmic Photon, Neutrino and Gravitational Wave Backgrounds. Amand Faessler , Erice September 2014 With thanks to : Rastislav Hodak , Sergey Kovalenko , Fedor Simkovic ;. Publication : arXiv : 1304.5632 [ nucl-th ];

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Amand Faessler , Erice September 2014 With thanks to : Rastislav Hodak ,

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  1. Can welook back totheOrigin ofourUniverse? Cosmic Photon, Neutrino and Gravitational Wave Backgrounds. Amand Faessler, Erice September 2014 Withthanksto: RastislavHodak, Sergey Kovalenko, Fedor Simkovic; Publication: arXiv: 1304.5632 [nucl-th]; arXiv: 1407.6504 [nucl-th] July 2014 and acceptedby EPJ Web ofConferences vol. 71; tobepublished J. Phys. G 2014.

  2. CosmicMicrowave Background Radiation Cosmic Neutrino Background CosmicGravitational Wave Background 1) Decouplingofthephotonsfrom matter about 380 000 years after the Big Bang, whentheelectronsarecapturedbytheprotons and He4 nucleiat a Temp. ofabout 3000 Kelvin. The universe was then neutral. Photons movefreely.

  3. Planck SatelliteTemperatureFluctuationsComic Microwave Background (Release March 21. 2013)

  4. On 18. March 2014 theBICEP2 Collaborationpublished in thearXiv: 1403.3985v2 [astro-ph.CO] Fingerprint oftheGravitationalWavesoftheInflationary Expansion ofthe Big Bang in theCosmic Background Radiation. GravitationalWavesareQuadrupole OscillationsofSpace not in Space.

  5. BICEP2 Detector at the South-Pole

  6. 1.5 to 4 degrees;

  7. 2) Estimateof Neutrino Decoupling Universe Expansion rate: H=(da/dt)/a • ~ n Interaction rate: G= ne-e+<svrelative> • H = = O( T2) [1/time] • ~ (1/a3) <GF2p2 c=1> ~ T3 <GF2T2c=1> ~ GF2T5[1/time] • with: Temperature= T ~ 1/a = 1/(lengthscale); = h/(2p) = c = 1 Stefan-Boltzmann

  8. HowcanonedetecttheCosmic Neutrino Background? Electron-Neutrino capture on Tritium.

  9. 3. Search forCosmic Neutrino Background CnBby Beta decay: Tritium Kurie-Plot of Beta andinduced Beta Decay: n(CB)+ 3H(1/2+)  3He (1/2+) + e- Infinite goodresolution Q = 18.562 keV Resolution Mainz: 4 eV  mn < 2.3 eV Emittedelectron Resolution KATRIN: 0.93 eV  mn < 0.2 eV 90% C. L. ElectronEnergy Fit parameters: mn2andQ valuemeV Additional fit: onlyintensityofCnB 2xNeutrino Masses

  10. Tritium Beta Decay: 3H 3He+e-+nce

  11. Neutrino Capture: n(relic) + 3H 3He + e- 20 mg(eff) of Tritium  2x1018 T2-Molecules: Nncapture(KATRIN) = 1.7x10-6nen/<nen> [year-1] Every 590 000 years a count! for <nen> = 56 cm-3

  12. Problem: 56 e-Neutrinos cm-3toosmall • Gravitational Clustering of Neutrinos estimatedby Y. Wong, P. Vogel et al.: nne(Galaxy) = 106*<nne> = 56 000 000 cm-3 1.7 counts per year Increasethsourcestrength: 20 micrograms 2 milligrams 170 counts per year everysecondday a count Speakersof KATRIN: Guido Drexlin and Christian Weinheimer

  13. 20 microgram 2 milligram Tritium • Such an IncreaseoftheTritium Source Intensityiswith a KATRIN Type Spectrometerisdifficult, if not impossible!

  14. ThreeimportantRequirements: • The Tritium DecayElectronsare not allowedtoscatterwiththe Tritium Gas. 2) The MagneticFlux must beconserved in the wholeDetection System. 3) The Energyresolution must beofthe order of 1 eV.

  15. The decayelectronsshould not scatterbythe Tritium gas. Only 36% have not scattered Source Beam Magnetic Field 3.6 Tesla Optimal Densityslightlybelowr*dfree/2 Tritium Gas Troitsk: 30%; Mainz: 40%; KATRIN: 90%

  16. 2) ConservationofMagneticFlux Ifonecantincreasetheintensity per area, increasethe areabyfactor 100 from 53 cm2to 5000 cm2. MagneticFlux: (Ai=5000 cm2) x (Bi=3.6 Tesla) = 18 000 Tesla cm2 = Af x (3 Gauss); Af= 6 000 m2 diameter = 97 meters

  17. 3) EnergyresolutionofDE~ 1 eV Energyresolution:Ef(perpend.) = Efp= DE

  18. Angular MomentumoftheSpiralingElectrons must beconserved Energyresolution:Ef(perpend.) = Efp= DE = 1 eV L = |rm = const = L ~ []i =[  Bf = 3 Gauss

  19. 20 microgram 2 milligram Tritium • Such an IncreaseoftheTritium Source Intensitywith a KATRIN Type Spectrometerisdifficult, if not impossible.

  20. Summary 1 • The CosmicMicrowave Background allowstostudytheUniverse 380 000 years after the BB. • The Cosmic Neutrino Background 1 sec after the Big Bang (BB). • The Cosmic Background ofGravitationalWaves 10-31 Seconds in the Big Bang

  21. Summary 2: CosmicNeutrino Background Average Density: nne= 56 [ Electron-Neutrinos/cm-3] Katrin: 1 Count in 590 000 Years Gravitational Clustering of Neutrinosnn/<nn> < 106 and 20 micrograms Tritium  1.7 counts per year. (2 milligram3H 170 counts per year. Impossible ?) THE END 2. Measureonly an upperlimitofnn Kurie-Plot Emittedelectron ElectronEnergy 2xNeutrino Masses

  22. Cyclotron Radiation Detectionof Tritium DecayElectrons. Phys. Rev. D80 (2009) 051301

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