413 research outputs found
Nucleon Edm from Atomic Systems and Constraints on Supersymmetry Parameters
The nucleon EDM is shown to be directly related to the EDM of atomic systems.
From the observed EDM values of the atomic Hg system, the neutron EDM can be
extracted, which gives a very stringent constraint on the supersymmetry
parameters. It is also shown that the measurement of Nitrogen and Thallium
atomic systems should provide important information on the flavor dependence of
the quark EDM. We perform numerical analyses on the EDM of neutron, proton and
electron in the minimal supersymmetric standard model with CP-violating phases.
We demonstrate that the new limit on the neutron EDM extracted from atomic
systems excludes a wide parameter region of supersymmetry breaking masses above
1 TeV, while the old limit excludes only a small mass region below 1 TeV.Comment: 10 pages, 7 figure file
Electric dipole moments of Hg, Xe, Rn, Ra, Pu, and TlF induced by the nuclear Schiff moment and limits on time-reversal violating interactions
We have calculated the atomic electric dipole moments (EDMs) induced in
^{199}Hg, ^{129}Xe, ^{223}Rn, ^{225}Ra, and ^{239}Pu by their respective
nuclear Schiff moments S. The results are (in units 10^{-17}S(e {fm}^{3})^{-1}e
cm): d(^{199}Hg)=-2.8, d(^{129}Xe)=0.38, d(^{223}Rn)=3.3, d(^{225}Ra)=-8.5,
d(^{239}Pu)=-11. We have also calculated corrections to the parity- and
time-invariance-violating (P,T-odd) spin-axis interaction constant in TlF.
These results are important for the interpretation of atomic and molecular
experiments on EDMs in terms of fundamental P,T-odd parameters.Comment: 16 page
Polarization and relaxation of radon
Investigations of the polarization and relaxation of Rn by spin
exchange with laser optically pumped rubidium are reported. On the order of one
million atoms per shot were collected in coated and uncoated glass cells.
Gamma-ray anisotropies were measured as a signal of the alignment (second order
moment of the polarization) resulting from the combination of polarization and
quadrupole relaxation at the cell walls. The temperature dependence over the
range 130C to 220C shows the anisotropies increasing with
increasing temperature as the ratio of the spin exchange polarization rate to
the wall relaxation rate increases faster than the rubidium polarization
decreases. Polarization relaxation rates for coated and uncoated cells are
presented. In addition, improved limits on the multipole mixing ratios of some
of the main gamma-ray transitions have been extracted. These results are
promising for electric dipole moment measurements of octupole-deformed
Rn and other isotopes, provided sufficient quantities of the rare
isotopes can be produced.Comment: 4 pages, 4 figure
Hadronic EDMs, the Weinberg Operator, and Light Gluinos
We re-examine questions concerning the contribution of the three-gluon
Weinberg operator to the electric dipole moment of the neutron, and provide
several QCD sum rule-based arguments that the result is smaller than - but
nevertheless consistent with - estimates which invoke naive dimensional
analysis. We also point out a regime of the MSSM parameter space with light
gluinos for which this operator provides the dominant contribution to the
neutron electric dipole moment due to enhancement via the dimension five color
electric dipole moment of the gluino.Comment: 6 pages, RevTeX, 3 figures; v2: references added; v3: typos
corrected, to appear in Phys. Rev.
Acetylcholinesterase of human erythrocytes and neuromuscular junctions: homologies revealed by monoclonal antibodies.
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
Surface Deformations as Indicators of Deep Ebullition Fluxes in a Large Northern Peatland
Peatlands deform elastically during precipitation cycles by small (+/- 3 cm) oscillations in surface elevation. In contrast, we used a Global Positioning System network to measure larger oscillations that exceeded 20 cm over periods of 4 - 12 hours during two seasonal droughts at a bog and fen site in northern Minnesota. The second summer drought also triggered 19 depressuring cycles in an overpressured stratum under the bog site. The synchronicity between the largest surface deformations and the depressuring cycles indicates that both phenomena are produced by the episodic release of large volumes of gas from deep semi-elastic compartments confined by dense wood layers. We calculate that the three largest surface deformations were associated with the release of 136 g CH4 m(-2), which exceeds by an order of magnitude the annual average chamber fluxes measured at this site. Ebullition of gas from the deep peat may therefore be a large and previously unrecognized source of radiocarbon depleted methane emissions from northern peatlands
Near-infrared spectroscopy detects age-related differences in skeletal muscle oxidative function: promising implications for geroscience
Age is the greatest risk factor for chronic disease and is associated with a marked decline in functional capacity and quality of life. A key factor contributing to loss of function in older adults is the decline in skeletal muscle function. While the exact mechanism(s) remains incompletely understood, age-related mitochondrial dysfunction is thought to play a major role. To explore this question further, we studied 15 independently living seniors (age: 72 ± 5 years; m/f: 4/11; BMI: 27.6 ± 5.9) and 17 young volunteers (age: 25 ± 4 years; m/f: 8/9; BMI: 24.0 ± 3.3). Skeletal muscle oxidative function was measured in forearm muscle from the recovery kinetics of muscle oxygen consumption using near-infrared spectroscopy (NIRS). Muscle oxygen consumption was calculated as the slope of change in hemoglobin saturation during a series of rapid, supra-systolic arterial cuff occlusions following a brief bout of exercise. Aging was associated with a significant prolongation of the time constant of oxidative recovery following exercise (51.8 ± 5.4 sec vs. 37.1 ± 2.1 sec, P = 0.04, old vs. young, respectively). This finding suggests an overall reduction in mitochondrial function with age in nonlocomotor skeletal muscle. That these data were obtained using NIRS holds great promise in gerontology for quantitative assessment of skeletal muscle oxidative function at the bed side or clinic
Angular Momentum Partitioning in the Dissociation of Diatomic Molecules
We discuss recent experiments that study the transfer of angular momentum from a projectile to the residual target in collisions between the simple diatomic molecules H2 and N2 and spin-polarized electrons or circularly-polarized photons. We observe the fluorescence of both the atomic fragments and excited molecular states, and measure the circular polarization fraction of this light, P3. The incident electron energies range from 10 to 100 eV; the incident photon energies from 33 to 38 eV
Glycoinositol phospholipid anchor and protein C-terminus of bovine erythrocyte acetylcholinesterase: analysis by mass spectrometry and by protein and DNA sequencing
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