Amand Faessler, Erice September 2014 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]; arXiv: 1407.6504 [nucl-th] July 2014 and accepted by EPJ Web of Conferences vol. 71; to be published J. Phys. G 2014.

Cosmic Microwave Background Radiation Cosmic Neutrino Background Cosmic Gravitational Wave Background 1) Decoupling of the photons from matter about 380 000 years after the Big Bang, when the electrons are captured by the protons and He4 nuclei at a Temp. of about 3000 Kelvin. The universe was then neutral. Photons move freely.

Planck Satellite Temperature Fluctuations Comic Microwave Background (Release March 21. 2013)

Gravitational Waves are Quadrupole Oscillations of Space not in Space. On 18. March 2014 the BICEP2 Collaboration published in the arXiv: 1403.3985v2 [astro-ph.CO] Fingerprint of the Gravitational Waves of the Inflationary Expansion of the Big Bang in the Cosmic Background Radiation. Gravitational Waves are Quadrupole Oscillations of Space not in Space.

BICEP2 Detector at the South-Pole

1.5 to 4 degrees; ℓ=40 𝑡𝑜 110

2) Estimate of Neutrino Decoupling Universe Expansion rate: H=(da/dt)/a ~ n Interaction rate: G= ne-e+<svrelative> H = 8π𝐺ρ𝑡𝑜𝑡𝑎𝑙/3 = O( T2) [1/time] ~ (1/a3) <GF2 p2 c=1> ~ T3 <GF2 T2c=1> ~ GF2 T5 [1/time] with: Temperature = T ~ 1/a = 1/(length scale); ℎ𝑏𝑎𝑟 = h/(2p) = c = 1 Stefan-Boltzmann

How can one detect the Cosmic Neutrino Background? Electron-Neutrino capture on Tritium.

3. Search for Cosmic Neutrino Background CnB by Beta decay: Tritium Kurie-Plot of Beta and induced Beta Decay: n(CB) + 3H(1/2+)  3He (1/2+) + e- Infinite good resolution Q = 18.562 keV Resolution Mainz: 4 eV  mn < 2.3 eV Emitted electron Resolution KATRIN: 0.93 eV  mn < 0.2 eV 90% C. L. Electron Energy Fit parameters: mn2 and Q value meV 2xNeutrino Masses Additional fit: only intensity of CnB

Tritium Beta Decay: 3H 3He+e-+nce

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

Problem: 56 e-Neutrinos cm-3 too small Gravitational Clustering of Neutrinos estimated by Y. Wong, P. Vogel et al.: nne(Galaxy) = 106*<nne> = 56 000 000 cm-3 1.7 counts per year Increase th source strength: 20 micrograms  2 milligrams 170 counts per year  every second day a count Speakers of KATRIN: Guido Drexlin and Christian Weinheimer

20 microgram  2 milligram Tritium Such an Increase of the Tritium Source Intensity is with a KATRIN Type Spectrometer is difficult, if not impossible!

Three important Requirements: The Tritium Decay Electrons are not allowed to scatter with the Tritium Gas. 2) The Magnetic Flux must be conserved in the whole Detection System. 3) The Energy resolution must be of the order of 1 eV.

The decay electrons should not scatter by the Tritium gas. Only 36% have not scattered Source Beam Magnetic Field 3.6 Tesla Tritium Gas Optimal Density slightly below r*dfree /2 Troitsk: 30%; Mainz: 40%; KATRIN: 90%

2) Conservation of Magnetic Flux If one cant increase the intensity per area, increase the area by factor 100 from 53 cm2 to 5000 cm2. Magnetic Flux: (Ai=5000 cm2) x (Bi=3.6 Tesla) = 18 000 Tesla cm2 = Af x (3 Gauss); Af = 6 000 m2  diameter = 97 meters

3) Energy resolution of DE~ 1 eV Energy resolution: Ef(perpend.) = Efp = DE

Angular Momentum of the Spiraling Electrons must be conserved Energy resolution: Ef(perpend.) = Efp = DE = 1 eV L = |r×𝐩|∝ m = const ∝ 𝐸𝑖𝑝 𝐵𝑖 = 𝐸𝑓𝑝 𝐵𝑓 L ~ [ 12 000 𝑒𝑉 36 000 𝐺𝑎𝑢𝑠𝑠 ]i =[ 1 𝑒𝑉 𝐵𝑓 ]𝑓  Bf = 3 Gauss

20 microgram  2 milligram Tritium Such an Increase of the Tritium Source Intensity with a KATRIN Type Spectrometer is difficult, if not impossible.

Summary 1 The Cosmic Microwave Background allows to study the Universe 380 000 years after the BB. The Cosmic Neutrino Background 1 sec after the Big Bang (BB). The Cosmic Background of Gravitational Waves 10-31 Seconds in the Big Bang

Summary 2: Cosmic Neutrino Background Average Density: nne = 56 [ Electron-Neutrinos/cm-3] Katrin: 1 Count in 590 000 Years Gravitational Clustering of Neutrinos nn/<nn> < 106 and 20 micrograms Tritium  1.7 counts per year. (2 milligram 3H 170 counts per year. Impossible ?) THE END 2. Measure only an upper limit of nn Kurie-Plot Electron Energy Emitted electron 2xNeutrino Masses

Cyclotron Radiation Detection of Tritium Decay Electrons. Phys. Rev Cyclotron Radiation Detection of Tritium Decay Electrons. Phys. Rev. D80 (2009) 051301