104 research outputs found
Measurement of the Muon Anomalous Magnetic Moment to 0.7 ppm
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
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 . 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 and the explicit breaking terms in the effective
potential and also anomaly terms for some non-Abelian gauge
groups . 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 in the
potential in which case the leading term suppressed by 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, is considered to
be smaller than , 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
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
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
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
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 spin precession frequency
and the background axion field oscillation to greatly enhance sensitivity to
it. An axion frequency range from Hz to 100 MHz can in principle be
scanned with high sensitivity, corresponding to an range of
GeV GeV, the breakdown scale of the global symmetry
generating the axion or axion like particles (ALPs)
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