Schiff moment of the mercury nucleus and the proton dipole moment

The Schiff moment of the ¹⁹⁹Hg nucleus is calculated using finite range P-and T-violating weak nucleon-nucleon interaction. Both the contributions of the P-and T-odd interaction and of internal nucleon electric dipole moments to the Schiff moment of ¹⁹⁹Hg are calculated. The contribution of the proton electric dipole moment is obtained via core-polarization effects treated in the framework of RPA with effective residual interactions. We derive a new upper bound |d _p |<5.4×10^?24e cm for the proton electric dipole moment.     

Polarized electric dipole moment of well-deformed reflection asymmetric nuclei

The expression for polarized electric dipole moment of well-deformed reflection asymmetric nuclei is obtained in the framework of the liquid-drop model in the case of geometrically similar proton and neutron surfaces. The expression for polarized electric dipole moment consists of the first- and second-order terms. It is shown that the second-order correction terms of the polarized electric dipole moment are important for well-deformed nuclei.     

R-parity violating contribution to the neutron electric dipole moment at one-loop order

We present the full result for the down squark mass-squared matrix in the complete theory of supersymmetry without R parity where all kinds of R-parity violating terms are admitted without bias using an optimal parametrization. The major result is a new contribution to LR squark mixing, involving both bilinear and trilinear R-parity violating couplings. Among other things, the latter leads to neutron electric dipole moment at one-loop level. Similar mechanisms lead to electron electric dipole moment at the same level. We present here a short report on major features of neutron electric dipole moment from supersymmetry without R parity and give the interesting constraints obtained.     

High-energy proton-irradiation effects on the charge transport and electric dipole moment of KH2PO4

We have studied the charge transport and dielectric properties of KH₂PO₄ (KDP) single crystals, irradiated by proton beams with high energies up to 20 MeV, by means of the temperature-dependent electrical conductivity and dielectric constant measurements. It is shown that the electrical conductivity and the electric dipole moment may be sensitively controlled by the proton irradiation energy and dose. The activation energy and the dipole moment were shown to be strongly correlated.     

Electron electric dipole moment induced by octet-colored scalars

An appended sector of two octet-colored scalars, each an electroweak doublet, is an interesting extension of the simple two Higgs doublet model motivated by the minimal flavor violation. Their rich CP violating interaction gives rise to a sizable electron electric dipole moment, besides the quark electric dipole moment via the two-loop contribution of Barr–Zee mechanism.     

Roton dipole moment

The roton excitation in the superfluid ⁴He does not possess a stationary dipole moment. However, a roton has an instantaneous dipole moment, such that at any given moment one can find it in the state either with positive or with negative dipole moment projection on its momentum direction. The instantaneous value of electric dipole moment of roton excitation is evaluated. The result is in reasonable agreement with recent experimental observation of the splitting of microwave resonance absorption line at roton frequency under external electric field.     

Reanalysis of the neutron electric dipole moment in Higgs models of CP-violation

We point out new contributions to the electric dipole moment of the neutron which arise in any model with spontaneous CP-violation. The effect is due to processes involving the exchange of a Higgs boson between the quarks constituting the neutron. In Weinberg's model, these new contributions are small compared to the single-quark contribution.     

New measurements of the neutron electric dipole moment

We report a new measurement of the neutron electric dipole moment with the PNPI EDM spectrometer using the ultracold neutron source PF2 at the research reactor of the ILL. Its first results can be interpreted as a limit on the neutron electric dipole moment of |d _n | < 5.5 × 10^?26 e cm (90% confidence level).     

Electric dipole moment of Dirac fermionic dark matter

The direct limit of electric dipole moment and direct searches for dark matter by electric dipole interaction are investigated with including the electromagnetic nuclear form factor, in case that the dark matter candidate is a Dirac particle. The electric dipole moment of dark matter constrained by direct searches must be lower than 7×¹⁰−22e cm for dark matter mass of 100 GeV to satisfy the current experimental exclusion limits at XENON10 and CDMS II. The CP violation of electric dipole moment and the dark matter discovery by electric dipole interaction in the future are considered.     

Electric dipole moment and chromoelectric dipole moment of the top quark inSU(3)C×SU(3)L×U(1)X model

We show that inSU(3) _C ×SU(3) _L ×U(1) _X model, the leading contribution to the electric and chromolelectric dipole moment of the top quark is due to the one-loop diagrams which come from exchanging the charged and neutral Higgs bosons. The dipole moments are typically of the order of 10^?19 e-cm and 10^?19 g-cm respectively, for the values of relative phases of the vev's such that CP violation is maximal. From an experimental point of view, theq ² dependence of dipole moment form factors is given.     

The dipole moment of the FO radical

The electric dipole moment of the FO radical (${}^2\text{Π}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$) has been directly measured by observing its saturated absorption laser magnetic resonance spectrum (v = 1 ← 0) in the presence of a moderate electric field. The resulting dipole moment [μ(v = 0) = 0.0043(4) D, μ(v = 1) = 0.0267(9) D] is extremely small, and shows a large relative change with vibrational state. The sign of the dipole moment is the same for the two vibrational states. Previous failures to detect microwave or gas phase EPR spectra of FO are fully explained by this small dipole moment.     

Mesoscopic fluctuations of the dipole moment and the electric polarizability

We consider mesoscopic fluctuations of the dipole moment and the electric polarizability of a disordered thin film in the diffusive regime. It is shown, that the requirement of a fixed particle number is crucial for obtaining finite fluctuations at low temperatures. For systems with sufficient disorder and a long screening length a spontaneous dipole moment should be observable with an atomic force microscope.Dedicated to Prof. H. Wagner on the occasion of his 60th birthday     

Time-reversal-violating generation of static magnetic and electric fields and a problem of electric dipole moment measurement

It is shown that in the experiments for the search of the electric dipole moment of an electron (atom, molecule) the T-odd magnetic moment induced by an electric field and the T-odd electric dipole moment induced by a magnetic field will be also measured. How to distinguish these contributions is discussed here.     

CP violation in gauge theories and the electric dipole moment of the neutron

A nonvanishing contribution to the neutron electric dipole moment in CP-violating gauge theories of the weak interactions, arising from interaction of the photon with two-quark subsystems of the three-bound-quark neutron system, is calculated. In the Kobayashi-Maskawa model the resulting value of the moment is estimated as O(10^?32) e cm; however, strong interaction corrections (gluonic radiative corrections) give quark moment contributions which may be numerically larger (possibly 10^?30±1 e cm). Either case clearly distinguishes gauge-sector CP violation from Higgs-sector CP violation which typically gives a neutron moment of order 10^?24 e cm.     

Electric dipole moment of the neutron in the electric field of a crystal

The effect of the weak interaction on the diffraction measurement of the electric dipole moment of neutrons moving in crystal electric fields has been analyzed. It has been shown that the interference of the Schwinger interaction with the weak interaction field imposes restrictions on the measured electric dipole moment of the neutron.     

Taking into account the Earth’s rotation in experiments on the search of the electric dipole moment of the neutron

The problem of taking into account the Earth’s rotation in the search of the electric dipole moment of the neutron in experiments with ultracold neutrons and in the diffraction experiment is analyzed. For the precision reached up to the present moment in the diffraction experiment, the account of the Earth’s rotation yields a negligible (exactly calculated) correction. In experiments with ultracold neutrons, this correction exceeds the systematic error of measurement of the electric dipole moment of the neutron, and its exact calculation requires additional investigations. In this regard, further development of the diffraction method should considerably promote the progress in the search of the electric dipole moment of the neutron.     

Contribution of the triangle graphs to the neutron electric dipole moment

In the Kobayashi-Maskawa model we compute a new contribution to the neutron electric dipole moment induced byCP violating flavour-changing transitions of the typess→d+gluon+γ through heavy quark loops. This contribution, essentially given by the triangle anomaly graph, is by itself gauge invariant. We obtain from this mechanismD _n /e=3.10^?32 cm, one order of magnitude below our previous estimate from usual penguin diagram contributions.     

Study of Top Quark FCNC

We study the one-loop contribution of the effective flavor changing neutral couplings (FCNC) tcZ on the charm quark electric dipole moment. Using the known limits on the top and charm quarks electric dipole moments, we place limits on these FCNC anomalous couplings.     

Critical electric dipole moment in one dimension

The magnitude of an electric dipole moment must be larger or equal to a certain value to support bound states. Such critical dipole moment, pcrit, has been calculated in 2 and 3 dimensions and has been suggested that its calculation in one dimension cannot be possible. We evaluate pcrit in one dimension showing that the previous suggestion is untenable.     

The electric dipole moment of the neutron in the Kobayashi-Maskawa model

A possible mechanism for producing a neutron electric dipole moment to order G_F² in the Kobayashi-Maskawa model is proposed; the consequent order of magnitude of the dipole moment would be 10^?30 cm in units of the electric charge.