575 research outputs found

    CP violation in K±π0π0π±K^{\pm}\to\pi^0\pi^0\pi^{\pm} decay

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    CP violation leads to a difference between the parameters g+g^+ and gg^- describing the energy distributions of the charged pions produced in the K+π0π0π+K^+ \to\pi^0 \pi^0 \pi^+ and Kπ0π0πK^- \to \pi^0\pi^0 \pi^- decays. We study the difference (g+g)(g^+ - g^-) as a function of the relative contributions from the QCD-penguin and the electroweak-penguin diagrams. We find that the combination of these contributions in (g+g)(g^+ - g^-) is very similar to the corresponding one defining the parameter ϵ\epsilon' in the KL2πK_L \to 2\pi decays. This observation allows a determination of the value of (g+g)(g^+ - g^-), using data on ϵ\epsilon'

    Kaon semileptonic decay (K_{l3}) form factors from the instanton vacuum

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    We investigate the kaon semileptonic decay (K_{l3}) form factors within the framework of the nonlocal chiral quark model from the instanton vacuum, taking into account the effects of flavor SU(3) symmetry breaking. We also consider the problem of gauge invariance arising from the momentum-dependent quark mass in the present work. All theoretical calculations are carried out without any adjustable parameter, the average instanton size (rho ~ 1/3 fm) and the inter-instanton distance (R ~ 1 fm) having been fixed. We also show that the present results satisfy the Callan-Treiman low-energy theorem as well as the Ademollo-Gatto theorem. Using the K_{l3} form factors, we evaluate relevant physical quantities. It turns out that the effects of flavor SU(3) symmetry breaking are essential in reproducing the kaon semileptonic form factors. The present results are in a good agreement with experiments, and are compatible with other model calculations.Comment: 12 pages, 3 figures, submitted to PR

    Quark Loop Contributions to Neutron, Deuteron, and Mercury EDMs from Supersymmetry without R parity

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    We present a detailed analysis of the neutron, deuteron and mercury electric dipole moment from supersymmetry without R parity, focusing on the quark-scalar loop contributions. Being proportional to top Yukawa and top mass, such contributions are often large. Analytical expressions illustrating the explicit role of the R-parity violating parameters are given following perturbative diagonalization of mass-squared matrices for the scalars. Dominant contributions come from the combinations Biλij1B_i \lambda^{\prime}_{ij1} for which we obtain robust bounds. It turns out that neutron and deuteron EDMs receive much stronger contributions than mercury EDM and any null result at the future deuteron EDM experiment or Los Alamos neutron EDM experiment can lead to extra-ordinary constraints on RPV parameter space. Even if R-parity violating couplings are real, CKM phase does induce RPV contribution and for some cases such a contribution is as strong as contribution from phases in the R-parity violating couplings.Hence, we have bounds directly on Biλij1|B_i \lambda^{\prime}_{ij1}| even if the RPV parameters are all real. Interestingly, even if slepton mass and/or μ0\mu_0 is as high as 1 TeV, it still leads to neutron EDM that is an order of magnitude larger than the sensitivity at Los Alamos experiment. Since the results are not much sensitive to tanβ\tan \beta, our constraints will survive even if other observables tighten the constraints on tanβ\tan \beta.Comment: 16 pages, 10 figures, accepted for publication in Physical Review

    Electric Dipole Moments of Leptons in the Presence of Majorana Neutrinos

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    We calculate the two-loop diagrams that give a non-zero contribution to the electric dipole moment d_l of a charged lepton l due to possible Majorana masses of neutrinos. Using the example with one generation of the Standard Model leptons and two heavy right-handed neutrinos, we demonstrate that the non-vanishing result for d_l first appears in order O(m_l m_\nu^2 G_F^2), where m_\nu is the mass of the light neutrino and the see-saw type relation is imposed. This effect is beyond the reach of presently planned experiments.Comment: 13 page

    Patterns Formation in Drying Drops of Blood

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    The drying of a drop of human blood exhibits coupled physical mechanisms, such as Marangoni flow, evaporation and wettability. The final stage of a whole blood drop evaporation reveals regular patterns with a good reproducibility for a healthy person. Other experiments on anaemic and hyperlipidemic people were performed, and different patterns were revealed. The flow motion inside the blood drop is observed and analyzed with the use of a digital camera: the influence of the red blood cells (RBCs) motion is revealed at the drop periphery as well as its consequences on the final stage of drying. The mechanisms which lead to the final pattern of the dried blood drops are presented and explained on the basis of fluid mechanics in conjunction with the principles of haematology. The blood drop evaporation process is evidenced to be driven only by Marangoni flow. The same axisymetric pattern formation is observed, and can be forecast for different blood drop diameters. The evaporation mass flux can be predicted with a good agreement, assuming only the knowledge of the colloids mass concentration.Comment: 1 page + conference APS 2011 (1 movie for the gallery + 1 movie for ArXiv

    CP-odd static electromagnetic properties of the W gauge boson and the t quark via the anomalous tbW coupling

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    In the framework of the electroweak chiral Lagrangian, the one-loop induced effects of the anomalous tbWtbW coupling, which includes both left- and right-handed complex components, on the static electromagnetic properties of the WW boson and the tt quark are studied. The attention is focused mainly on the CP-violating electromagnetic properties. It is found that the tbWtbW anomalous coupling can induce both CP-violating moments of the WW boson, namely, its electric dipole (μ~W\tilde{\mu}_W) and magnetic quadrupole (Q~W\tilde{Q}_W) moments. As far as the tt quark is concerned, a potentially large electric dipole moment (dt)(d_t) can arise due to the anomalous tbWtbW coupling. The most recent bounds on the left- and right-handed parameters from BB meson physics lead to the following estimates μ~W 10231022\tilde{\mu}_W ~ 10^{-23}-10^{-22} e-cm and Q~W 10381037\tilde{Q}_W~ 10^{-38}-10^{-37} e-cm2^2, which are 7 and 14 orders of magnitude larger than the standard model (SM) predictions, whereas dtd_t may be as large as 102210^{-22} e-cm, which is about 8 orders of magnitude larger than its SM counterpart.Comment: This paper has been merged with hep-ph/0612171 for publication in Physical Review

    Two-loop gluino contributions to neutron electric dipole moment in CP violating MSSM

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    We analyze two-loop gluino corrections to the neutron electric dipole moment (EDM) in the minimal supersymmetry extension of the standard model (MSSM). The dependence of two-loop corrections on the relevant CP violating phases differs from that of the one-loop contributions, and there is a region in the parameter space where the two-loop contributions are comparable with the one-loop contributions. Our numerical results show that the two-loop corrections can be as large as 30% of the one-loop results.Comment: Revtex, 27 pages, including 11 ps figure

    Electric dipole and magnetic quadrupole moments of the WW boson via a CP-violating HWWHWW vertex in effective Lagrangians

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    The possibility of nonnegligible WW electric dipole (μ~W\widetilde{\mu}_W) and magnetic quadrupole (Q~W\widetilde{Q}_W) moments induced by the most general HWWHWW vertex is examined via the effective Lagrangian technique. It is assumed that new heavy fermions induce an anomalous CP-odd component of the HWWHWW vertex, which can be parametrized by an SUL(2)×UY(1)SU_L(2)\times U_Y(1)-invariant dimension-six operator. This anomalous contribution, when combined with the standard model CP-even contribution, lead to CP-odd electromagnetic properties of the WW boson, which are characterized by the form factors Δκ~\Delta \widetilde{\kappa} and ΔQ~\Delta \widetilde{Q}. It is found that Δκ~\Delta \widetilde{\kappa} is divergent, whereas ΔQ~\Delta \widetilde{Q} is finite, which reflects the fact that the latter cannot be generated at the one-loop level in any renormalizable theory. Assuming reasonable values for the unknown parameters, we found that μ~W36×1021\widetilde{\mu}_W\sim 3-6\times 10^{-21} e-cm, which is eight orders of magnitude larger than the SM prediction and close to the upper bound derived from the neutron electric dipole moment. The estimated size of the somewhat less-studied Q~W\widetilde{Q}_W moment is of the order of 1036-10^{-36} e-cm^2, which is fifteen orders of magnitude above the SM contribution.Comment: 7 pages, 6 figures, REVTEX styl

    The neutron electric dipole form factor in the perturbative chiral quark model

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    We calculate the electric dipole form factor of the neutron in a perturbative chiral quark model, parameterizing CP-violation of generic origin by means of effective electric dipole moments of the constituent quarks and their CP-violating couplings to the chiral fields. We discuss the relation of these effective parameters to more fundamental ones such as the intrinsic electric and chromoelectric dipole moments of quarks and the Weinberg parameter. From the existing experimental upper limits on the neutron EDM we derive constraints on these CP-violating parameters.Comment: 20 pages, 3 figure

    Characterization of Spatial Coherence of Synchrotron Radiation with Non-Redundant Arrays of Apertures

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    We present a method to characterize the spatial coherence of soft X-ray radiation from a single diffraction pattern. The technique is based on scattering from non-redundant arrays (NRA) of slits and records the degree of spatial coherence at several relative separations from one to 15 microns, simultaneously. Using NRAs we measured the transverse coherence of the X-ray beam at the XUV X-ray beamline P04 of the PETRA III synchrotron storage ring as a function of different beam parameters. To verify the results obtained with the NRAs additional Young's double pinhole experiments were conducted and show good agreement.Comment: 15 pages, 6 figures, 2 tables, 42 reference
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