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High Precision Experiments with Cold and Ultra-Cold Neutrons Hartmut Abele Vienna, 1 December 2012 qB OUNCE : Spectroscopy of Gravity |1 > 1.4 peV |3 > 3.32 peV a, A, B, C
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Show Case I: Test of Gravitation at Short Distances with Quantum I nterference Julio Gea-Banacloche, Am. J. Phys.1999 Quantum interference: sensitivity to fifth forces Hartmut Abele, Atominstitut, TU Wien Time Rafael Reiter, Bernhard Schlederer, David Sepp Simulation: Reiter, Schlederer, Seppi Height, 40 µm
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Key Technique: Gravity Resonance Spectroscopy 3 atomic clocks nuclear magnetic resonance spectroscopy spin echo technique quantum metrology gamma resonance spectroscopy Test Newton‘s law at short distances: String Theories Dark Matter Dark Energy |1 > 1.4 peV |3 > 3.32 peV Nature Physics, 1 June 2011 High Precision - Low Energy Hartmut Abele, Atominstitut, TU Wien
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Rabi-Gravity-Spectroscopy GRS: T.J., H.A. et al., Nature Physics 2011 4 |1 > 1.4 peV |3 > 3.32 peV a 2-level system can be considered as a Spin ½ - System Vibrating mirror Alternating Magnetic gradient fields QS: V.N., H.A. et al., Nature 2002
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Side-band excitation Gähler, Felber, Golub et al. 5
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The kicked rotor M. Bienert, F. Haug and W. P. Schleich, Raizen 6 Hartmut Abele, Vienna University of Technology
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Gravity Resonance Spectroscopy -Quantum states in the gravity potential of the earth and coherence superposition Search for deviations from Newtons gravity law at short distances -Large extra dimensions -Dark matter particles -Dark energy Tests of weak interaction with neutron beta-decay experiments -Experiment PERC Scientific Programme for ESS /Broad overview of the field Outline 7
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Spallation Source Reactor source Neutron sources
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9 Hartmut Abele, Technische Universität Wien
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Neutron Production 10 10 -7 Velocity v [m/s]
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The future: FRM2, ESS 11
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Tool: Ultra-Cold Neutrons Strong Interaction: V ~ 100 neV Kinetic Energy: < 100 neV 3m/s < v < 20m/s Magnetism, Zeeman splitting : 120 neV/T Energy in the earth‘s gravitational field: E = mgh 100neV/m
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Hartmut Abele, Technische Universität München 13 Hartmut Abele 13 Quantum Bounce ? Cold-Source at 40 K Hydrogen Atom -Electron bound in proton potential -Bohr radius = 1 A -Ground state energy of 13 eV -3 dim. -Schrödinger Equ. -Legrendre Polynomials System Neutron & Earth -Neutron bound in the gravity potential of the earth - = 6 µm -Ground state energy of 1.4 peV -1 dim. -Schrödinger Equ. -Airy Functions
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Gravity and Quantum Mechanics 14 Schrödinger equation : boundary conditions: with 2nd mirror at height Solutions: Airy-functions: Ai & Bi EnEn EnEn 1 st state 1.41peV 2 nd state 2.46peV2.56peV 3 rd state 3.32peV4.2 peV V [peV]
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Show Case I: Rabi-type Spectroscopy of Gravity 15 Resonance Spectroscopy Technique to explore gravity T. Jenke, SPP1491-Treffen 2012, Frauenchiemsee
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neutron mirror UCN State Selection by a rough neutron mirror 4.5 days of beam time 3600 events (background subtracted) fit: free parameters: result: track detector rough mirror T. Jenke, ÖPG 2012
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6 m/s < v x < 7.2 m/s Horizontal velocity 17 Hartmut Abele, Technische Universität München T. Jenke, Diploma thesis, 2008
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Frequency Reference for Gravitation Hartmut Abele, Vienna University of Technology 18 |1 > 1.4 peV |3 > 3.32 peV Based on natural constants: ⁻Mass of the neutron m ⁻Planck constant ħ ⁻Acceleration of earth g ⁻ Based on 2 natural constants : ⁻Mass of the neutron m ⁻Planck constant ħ Plus Acceleration of earth g
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Discoveries: the dark universe Spectroscopy of Gravity -It does not use electromagnetic forces -It does not use coupling to em Potential Hyothetical gravity-like forces - Axions? - Chameleons? constraint on any possible new interaction 19 Axion 10 -14 eV Scale
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21 Felicitas Pauss
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The cosmological Parameters
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Neutrons test Newton Strength Range 23 Hypothetical Gravity Like Forces Extra Dimensions: The string and D p -brane theories predict the existence of extra space-time dimensions Infinite-Volume Extra Dimensions: Randall and Sundrum Exchange Forces from new Bosons: a deviation from the ISL can be induced by the exchange of new (pseudo)scalar and (pseudo)vector bosons Axion - - - - - - - - - - - - - - - - - - - → 0.2 µm < < 0.2 cm Scalar boson. Cosmological consideration Bosons from Hidden Supersymmetric Sectors Gauge fields in the bulk (ADD, PRD 1999) - - - - →10 6 < < 10 9 Supersymmetric large Extra Dimensions (B.& C.) - - - - → < 10 6 Chameleon fields-
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Show Case: Rabi-type Spectroscopy of Gravity 24 Rabi-type experiment: Resonance Spectroscopy Technique to explore gravity realization of gravity resonance method possible simple setup, no steps high(er) transmission upper mirror introduces 2 nd boundary condition Rabi-type experiment with damping T. Jenke, SPP1491-Treffen 2012, Frauenchiemsee
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Gravity Resonance Spectroscopy 2012 25 50 days of beam time, 116 measurements stat. Significance: stat. accuracy: contrast: T. Jenke, Dissertation (TU Wien, 2011) T. Jenke et.al., arXiv:1208.3875 (2012) [data 2010] T. Jenke, ÖPG 2012 10 -14 eV Scale
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AXION: PDG Exclusion Ranges 26
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PDG Exclusion Ranges on Axion masses 27 ← ←
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Applications I: Spin-dependant short-ranged interactions 28 discovery potential [Setup 2010]: J.E. Moody, F. Wilczek, Phys. Rev. D30, 131-138 (1984) 3 days of beamtime T. Jenke et.al., arXiv:1208.3875 (2012) T. Jenke, ÖPG 2012
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Chameleon fields, Brax et al. PRD 70, 123518 (2004) 2 Parameters , n Dark Energy – Scalar Fields 29
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Mirrors at z ~ ± d/2 Fit to numerical solution qBounce and Chameleons
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Bounds on coupling -By comparing transition frequency with theoretical expectation: -as long as > 10 5 -Cite as: arXiv:1207.0419v1 qBounce and Chameleons
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Applications II: Strongly coupled chameleons 32 A.N. Ivanov et.al., arXiv:1207.0419 (2012) T. Jenke et.al., arXiv:1208.3875 (2012) T. Jenke, ÖPG 2012
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Feedback from FUNDAMENTAL PHYSICS Convener: T. Soldner, O. Zimmer, H. Abele
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Chameleon fields, Brax et al. PRD 70, 123518 (2004) 2 Parameters , n Dark Energy – Scalar Fields 34
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Casimir Force Atom Example Rb r = 1 Micron Neutron: Casimir force absent Polarizability extremely small: 35
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Grand Challenges 36 Sensitive to any force Dark energy search -chameleon fields Dark matter search Large extra dimensions Hypothetical gravity like forces
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Participating Institutions: IST Braunschweig Univ. Heidelberg ILL Univ. Jena Univ. Mainz Priority Areas CP-symmetry violation and particle physics in the early universe. The structure and nature of weak interaction and possible extensions of the Standard Model. Tests of gravitation with quantum objects Charge quantization and the electric neutrality of the neutron. New Infrastructure (UCN-Source, cold Neutrons) -* Coordinators (S. Paul, H.A. ) DFG/FWF Priority Programme 1491 Exzellenzcluster ‚Universe‘ München Techn. Univ. München * PTB Berlin Vienna University of Technology *
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Priority Programme 1491 Research Area A: CP-symmetry violation and particle physics in the early universe -Neutron EDM E = 10 -23 eV Research Area B: The structure and nature of weak interaction and possible extensions of the Standard Model -Neutron -decay V – A Theory Research Area C: Relation between gravitation and quantum theory -Neutron bound gravitational quantum states Research Area D: Charge quantization and the electric neutrality of the neutron -Neutron charge Research Area E: New measuring techniques -Particle detection -Magnetometry -Neutron optics
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39 Parameters Strength: G F Quark mixing: V ud Ratio: = g A /g V Observables Lifetime Correlation A Correlation B Correlation C Correlation a Correlation D Correlation N Correlation Q Correlation R Beta Spectrum Proton Spectrum Polarized Spectra Beta Helicity Electron Proton Neutrino Neutron Spin A B C a D R N Neutron Alphabet deciphers the SM High Precision - Low Energy Hartmut Abele, Atominstitut, TU Wien R Q
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v- selector Spin flipper Polarizer Decay Volume, 8m Chopper Beam stop Analyzing area A clean, bright and versatile source of neutron decay products Univ.Heidelberg & TU Wien, Mainz, ILL,FRM2,TU Munich n-guide + solenoid: field B 0 polarized, monochromatic n-pulse n + γ-beam stop solenoid, field B1 solenoid, field B 2 p+ + e− window-frame p+ + e− beam B. Maerkisch talk Berlin 2012 Key Instrument: PERC High Flux : = 2 x 10 10 cm -2 s -1 Decay rate of 1 MHz / metre Polarizer: 99.7 ± 0.1 % Spin Flipper: 100.05 ± 0.1 % Analyzer: 100 % 3 He-cells
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41 Origin of nature’s lefthandedness Standard Model: Elektroweak interaction 100% lefthanded Grand unified theories: Universe was left-right symmetric at the beginning Parity violation = 'emergent' Order parameter <100% Neutron decay: Correlation B + A: Mass right handed W-Boson: m R > 280 GeV/c 2 Phase: -0.20 < < 0.07 WLWL WRWR
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Grand Challenges 42 Sensitive to any theory beyond the Standard Model Left Right Symmetry Supersymmetry Tensor or scalar interactions GUT
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Priority Programme 1491 Research Area A: CP-symmetry violation and particle physics in the early universe -Neutron EDM Research Area B: The structure and nature of weak interaction and possible extensions of the Standard Model -Neutron -decay Research Area C: Relation between gravitation and quantum theory -Neutron bound gravitational quantum states Research Area D: Charge quantization and the electric neutrality of the neutron -Neutron charge Research Area E: New measuring techniques -Particle detection -Magnetometry -Neutron optics
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The Future: Ramsey-Method Hartmut Abele, Vienna University of Technology 44
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Since the Standard Model value for q n requires extreme fine tuning, the smallness of this value may be considered as a hint for GUTs, where q n is equal to zero. Improve limit by two orders of magnitude Charge quantization and the electric neutrality of the neutron.
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Progress Report with Galileo in Quantum Land -qBounce: first demonstration of the quantum bouncing ball -Dynamics: time evolution of coherent superposition of Airy-eigenfunctions - Realization of Gravity Resonance Spectroscopy: -Coherent Rabi-Transitions, -|1> |2> -|1> |3>, see Nature Physics, 1 June 2011 -|2> |3>, |2> |4> -New Tool for -A Search for a deviation from Newton‘s Law at short distances, where polarizability effects are extremely small, see H.A. et al., PRD 81, 065019 (2010) [arXiv:0907.5447 ] -A quantum test of the equivalence principle -Direct limits on axion coupling / chameleons at short distances, qB OUNCE Summary 46 Hartmut Abele, Vienna University of Technology
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