104 research outputs found

    Measurement of the Muon Anomalous Magnetic Moment to 0.7 ppm

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    The experimental method together with the analysis method and results of the data taken in 2000 and prospects of the muon anomalous magnetic and electric dipole moment experiments are presented here.Comment: 12 pages, 20 figures. Proceedings of my plenary talk at ICHEP02, Amsterdam, 31 July 200

    Fate of global symmetries in the Universe: QCD axion, quintessential axion and trans-Planckian inflaton decay-constant

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    Pseudoscalars appearing in particle physics are reviewd systematically. From the fundamental point of view at an ultra-violat completed theory, they can be light if they are realized as pseudo-Goldstone bosons of some spontaneously broken global symmetries. The spontaneous breaking scale is parametrized by the decay constant ff. The global symmetry is defined by the lowest order terms allowed in the effective theory consistent with the gauge symmetry in question. Since any global symmetry is known to be broken at least by quantum gravitational effects, all pseudoscalars should be massive. The mass scale is determined by ff and the explicit breaking terms ΔV\Delta V in the effective potential and also anomaly terms ΔΛG4\Delta\Lambda^4_G for some non-Abelian gauge groups GG. The well-known example by non-Abelian gauge group breaking is the potential for the "invisible" QCD axion, via the Peccei-Quinn symmetry, which constitutes a major part of this review. Even if there is no breaking terms from gauge anomalies, there can be explicit breaking terms ΔV\Delta V in the potential in which case the leading term suppressed by ff determines the pseudoscalar mass scale. If the breaking term is extremely small and the decay constant is trans-Planckian, the corresponding pseudoscalar can be a candidate for a `quintessential axion'. In general, (ΔV)1/4(\Delta V)^{1/4} is considered to be smaller than ff, and hence the pseudo-Goldstone boson mass scales are considered to be smaller than the decay constants. In such a case, the potential of the pseudo-Goldstone boson at the grand unification scale is sufficiently flat near the top of the potential that it can be a good candidate for an inflationary model, which is known as `natural inflation'. We review all these ideas in the bosonic collective motion framework.Comment: 41 pages with 27 figure

    A hybrid ring design in the storage-ring proton electric dipole moment experiment

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    A new, hybrid design is proposed to eliminate the main systematic errors in the frozen spin, storage ring measurement of the proton electric dipole moment. In this design, electric bending plates steer the particles, and magnetic focusing replaces electric. The magnetic focusing should permit simultaneous clock-wise and counter-clock-wise storage to cancel systematic errors related to the out-of-plane dipole electric field. Errors related to the quadrupole electric fields can be eliminated by successive runs of magnetic focusing with different strengths.Comment: 6 pages, 8 figure

    Concept of multiple-cell cavity for axion dark matter search

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    In cavity-based axion dark matter search experiments exploring high mass regions, multiple-cavity design is considered to increase the detection volume within a given magnet bore. We introduce a new idea, referred to as multiple-cell cavity, which provides various benefits including a larger detection volume, simpler experimental setup, and easier phase-matching mechanism. We present the characteristics of this concept and demonstrate the experimental feasibility with an example of a double-cell cavity.Comment: 8 pages, 11 figure

    Horn-array haloscope for volume-efficient broadband axion searches

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    The invisible axion is a hypothetical particle that arises from the Peccei-Quinn mechanism proposed to resolve the CP problem in quantum chromodynamics, and is considered one of the most favoured candidates for cold dark matter. Dish antennas can provide a useful scheme for sensitive search for dark matter axions. The conversion power through axion-photon couplings is proportional to the surface area of the metal plate, rather than the volume of the available magnetic field. To maximize the effect, we propose an advanced concept of haloscope that involves an array of horn antennae to increase the axion-induced photons and a reflector to focus them onto a photo sensor. Compared to other proposed schemes, this configuration can significantly improve the experimental sensitivity, especially in the terahertz region.Comment: 5 pages, 5 figure

    Axion dark matter search using the storage ring EDM method

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    We propose using the storage ring EDM method to search for the axion dark matter induced EDM oscillation in nucleons. The method uses a combination of B and E-fields to produce a resonance between the g−2g-2 spin precession frequency and the background axion field oscillation to greatly enhance sensitivity to it. An axion frequency range from 10−910^{-9} Hz to 100 MHz can in principle be scanned with high sensitivity, corresponding to an faf_a range of 101310^{13} GeV ≤fa≤1030\leq f_a \leq 10^{30} GeV, the breakdown scale of the global symmetry generating the axion or axion like particles (ALPs)
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