Electric and anomalous magnetic dipole moments of the muon in the mssm. Lee roberts, welcome and overview lepton moments 2006 19 june 2006p 2. I also discuss a new proposal to search for a permanent electric dipole moment edm of the muon and put it into the more general context of. The most precise determinations of lepton dipole moments are performed as measurements of spinprecession frequency, a technique favouring particles with longer lifetimes. Being vectors, these can reinforce or cancel each other, depending on the geometry of the molecule. Wboson magnetic dipole and electric quadrupole moments. Barrzee and lightbylight loop effects from a light pseudoscalar alplease note thathp are found to be capable of resolving the longstanding muon g2 discrepancy at the expense of relatively large alp couplings. An overview of the role of the muon magnetic moment in the study of physics beyond the standard model is given. The effects of lepton kk modes on the lepton electric. Polarization can thus be regarded as the electric dipole moment q0dper unit volume v of the material.
With the lone pair on the most electronegative atom in both cases we would then expect similar dipole moments the charge on our deprotonated pyrrole would exist independently of the dipole moment. An analysis of the electric dipole moment edm of the neutron and of the lepton in the minimal supersymmetric standard model mssm with the most general allowed set of cp violating phases without generational mixing is given. Order of magnitude smaller limit on the electric dipole. From the famous experiments of stern and gerlach to the present, measurements of magnetic dipole moments, and searches for. The method consists in studying the spin precession induced by the strong e ective magnetic eld inside channels of a bent crystal with a dedicated setup at the cern large hadron collider.
The theory predictions are a very good prospect for probing the dipole moments of the taulepton. The 15th international workshop on tau lepton physics. This chapter of the report of the flavor in the era of the lhc workshop discusses the theoretical, phenomenological and experimental issues related to flavor phenomena in the charged lepton sector and in flavor conserving cpviolating processes. Leptonflavor violation and two loop electroweak corrections to g2 in the bl symmetric ssm jinlei yang et althis content was downloaded from ip address 207. Contributions of a spin0 axionlike particle alp to lepton dipole moments, g2 and edms are examined. All these observables are induced by the same amplitude t ieo. The electric dipole moment is a measure of the separation of positive and negative electrical charges within a system, that is, a measure of the systems overall polarity.
We study the lepton electric dipole moments in the framework of the supersymmetric type ii seesaw model where the exchange of heavy su2w triplets generates small neutrino masses. Among these leptons, the electron is most accessible to experimental observation. We study the constraints that can be placed on anomalous. Neutron and lepton electric dipole moments in the minimal supersymmetric standard model, large cp violating phases, and the cancellation mechanism tarek ibrahim department of physics, northeastern university, boston, massachusetts 02115 and department of physics, faculty of science, university of alexandria, alexandria, egypt pran nath. Lepton dipole moments advanced series on directions in high energy physics published vol. In many models of cp violation, the electric dipole moments edms of leptons scale as the cube of the lepton mass. Contributions of very different types of physics beyond the standard model are compared on a general level. The analysis includes the contributions from the gluino, the chargino and the neutralino exchanges to the electric dipole operator, the chromoelectric dipole operator. Lepton dipole moments in extended technicolor models. P 1 v xn j1 j11 where nis the number of molecular dipole moments in volume v.
Electric dipole moments edms and new particle physics. Neutron and lepton electric dipole moments in the minimal. We study the charged lepton electric dipole moments in the randallsundrum model where the leptons and the gauge fields are accessible to the extra dimension. Pdf scaling of lepton dipole moments with lepton mass. In quantum electrodynamics, the anomalous magnetic moment of a particle is a contribution of effects of quantum mechanics, expressed by feynman diagrams with loops, to the magnetic moment of that particle. We analyze the diagonal and transition magnetic and electric dipole moments of charged leptons in extended technicolor etc models, taking account of the multiscale nature of the etc gauge symmetry breaking, conformal walking behavior of the technicolor. The dipole moments of the leptons and quarks are matrices in flavor space, which can potentially reveal as much about the flavor structure of the theory as do the mass matrices. Electric and anomalous magnetic dipole moments of the. Determining the fine structure constant chapter 6 in lepton dipole moments g. Pdf lepton dipole moments in extended technicolor models. The dipole moment is defined as the vector the dipolemoment magnitude p qs determines the electric field strength.
We show that the cp violating phase of the bilinear soft supersymmetry breaking term associated with the su2w triplets contributes to lepton electric dipole moments mainly through threshold corrections to the. Determining the fine structure constant chapter 6 in. While in many models the dipole moments scale roughly as lepton mass, it is shown that simple models exist in which the dipoles scale as the cube of the mass or in other ways. Lepton dipole moments in supersymmetric lowscale seesaw models. Neutrino cp phases and lepton electric dipole moments in. I also discuss a new proposal to search for a permanent electric dipole moment edm of the muon and put it into the more general context of other edm searches. Example feynman diagram of a np contribution to a magnetic. The precession angle is measured with a readout laser and fluorescence detection.
Lepton electric dipole moment and strong cp violation. Lepton dipole moment experiments are reaching levels of sensitivity that will make or break theories roberts and marciano have put together an excellent survey of lepton dipole moments and their certain power to change our world view whatever may come. The electric dipole moment of the electron funding nsf. Among these leptons, the electron is most accessible to. We analyze the scaling of the leptonic dipole moments with the lepton masses in theories beyond the standard model. Lepton electric dipole moments in supersymmetric type ii. Prospects for a millionfold improvement in the comparison of the antiproton and proton magnetic moments pdf 11. In this talk i discuss the progress on measurements and theory of the magnetic dipole moments of the electron and muon. Lepton dipole moments advanced series on directions in. Abstract from the famous experiments of stern and gerlach to the present, measurements of magnetic dipole moments, and searches for electric dipole. Introduction and theory of the lepton anomalies over the past 82 years, the study of dipole moments of elementary particles has provided a wealth of information on subatomic physics. We observe that the electric dipole moment of the electron muon. Publisher summarythis chapter discusses the electric dipole moments of lepton. The dirac magnetic moment, corresponding to treelevel feynman diagrams.
Slacpub10440 may, 2004 hepph0405214 the contribution from neutrino yukawa couplings to lepton electric dipole moments yasaman farzan1,2,3 and michael e. We study the charged lepton electric dipole moments in the randall sundrum model where the leptons and the gauge fields are accessible to the extra dimension. The effects of lepton kk modes on the electric dipole. Lepton dipole moments in supersymmetric lowscale seesaw. Physics department, university of california at berkeley.
We analyze the diagonal and transition magnetic and electric dipole moments of charged leptons in extended technicolor etc models, taking account of the multiscale nature of the etc gauge. We start by studying the supersymmetric contributions to the lepton edm and lepton flavour violation processes tau mu gamma and mu e gamma, in the framework of the mass insertion approximation, showing that, due to the large neutrino mixing, mu e gamma. The magnetic moment, also called magnetic dipole moment, is a measure of the strength of a magnetic source. In such experiments an applied magnetic or electric eld exerts a torque on the dipole moment, and hence on the spin, causing it to precess about the applied eld. But the actual pyrrole has that proton attached, at what would be the negative end of the furanlike dipole. Brookhaven national laboratory, usa lel world scientific. Sensitivity on the electromagnetic dipole moments of the. Lepton dipole moments and light scalar dark matter as windows to go beyond the standard model antonio masiero infn and univ. Feasibility of lepton electromagnetic dipole moments. Dipole moments as vector sums in molecules containing more than one polar bond, the molecular dipole moment is just the vector combination of what can be regarded as individual bond dipole moments.
When the material consists of individual dipoles j, the dipole moment per unit volume pshould correspond to the vector sum. Wolfgang quint gsi darmstadt this talk is cancelled because of visa problems with the us dohs. One can learn more by exploiting the association between the electric dipole moments of the electron and wboson, dsme and d. Contributions of axionlike particles to lepton dipole moments. Peskin1,3 1stanford linear accelerator center 2575 sand hill road, menlo park, california 94025 usa. From the famous experiments of stern and gerlach to the present, measurements of magnetic dipole moments, and searches for electric dipole moments of elementary particles have. We use an effective lagrangian description for physics beyond the standard model which contains the.
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