Anomalous Magnetic Moment Term Research Articles

Tests of hypercubic fermion actions

I have performed scaling tests using quenched spectroscopy of a family of fermion actions which have a hypercubic kinetic term, gauge connections built of smeared links, and an anomalous magnetic moment term. These actions show improved rotational invariance compared to the standard Wilson action and to the tadpole-improved clover action. Hyperfine splittings are improved compared to the standard Wilson action (at the level of a factor of three in the lattice spacing), and are about the same as for the tadpole-improved clover action.

On quantum corrections to Chern-Simons spinor electrodynamics

We make a detailed investigation on the quantum corrections to Chern-Simons spinor electrodynamics. Starting from Chern-Simons spinor quantum electrodynamics with the Maxwell term \(-1/(4\gamma){\int}d^3x F_{\mu\nu}F^{\mu\nu}\) and by calculating the vacuum polarization tensor, electron self-energy and on-shell vertex, we explicitly show that the Ward identity is satisfied and hence verify that the physical quantities are independent of the procedure of taking \({\gamma}{\to}{\infty}\) at tree and one-loop levels. In particular, we find the three-dimensional analogue of the Schwinger anomalous magnetic moment term of the electron produced from the quantum corrections.

Scaling tests of some lattice fermion actions

I describe studies of quenched spectroscopy, using crude approximations to fixed point actions for fermions interacting with SU(3) gauge fields. These actions have a hypercubic kinetic term and a complicated lattice anomalous magnetic moment term. They show improved scaling compared to the conventional Wilson action.

On quantum corrections to Chern-Simons spinor electrodynamics

We make a detailed investigation on the quantum corrections to Chern-Simons spinor electrodynamics. Starting from Chern-Simons spinor quantum electrodynamics with the Maxwell term $-1/(4\gamma){\int}d^3x F_{\mu\nu}F^{\mu\nu}$ and by calculating the vacuum polarization tensor, electron self-energy and on-shell vertex, we explicitly show that the Ward identity is satisfied and hence verify that the physical quantities are independent of the procedure of taking ${\gamma}{\to}{\infty}$ at one-loop and tree levels. In particular, we find the three-dimensional analogue of the Schwinger anomalous magnetic moment term of the electron produced from the quantum corrections.

On the Dirac equation with anomalous magnetic moment term in a beam of electromagnetic wave

The object of the paper is to obtain the solution of the Dirac equation with the Pauli-term in an electromagnetic field depending on the single variable (ct -nr) along the directionn.

On the Dirac equation with anomalous magnetic moment term and a plane electromagnetic field

We solve the non-minimally coupled Dirac equation for a particle with an anomalous magnetic moment in the presence of a plane electromagnetic wave, directly and from first principles. The exact wavefunction, obtained in this way, is shown to reduce to the Volkov state when the particle's anomaly is set equal to zero. Other limiting cases are also considered and their importance is pointed out.

On the gyromagnetic ratio in the Kaluza-Klein theories and the Schuster-Blackett law

Pauli's five-dimensional Dirac equation in projective space, which results in an anomalous magnetic moment term in four dimensions, is related to the Schuster-Blackett law of the magnetic field of rotating bodies and to the recent results on the gyromagnetic ratio in Kaluza-Klein theories.

The nucleon anomalous magnetic moment and meson exchange current operators

Abstract The anomalous magnetic moment term in the nucleon electromagnetic current operator leads to an important correction to the pion and ϱ -meson exchange current operators. The additional term is essential for quantitative predictions of the backward deuteron electrodisintegration cross section and the magnetic form factors of the trinucleons.

Scaling behaviour of charged spin-one partons in a gauge model

In a hadron model in which the fermion constituents are bound by vector-isovector gauge fields, electromagnetism is introduced; by spontaneously breaking the strong (SU(2)) gauge symmetry, the gauge fields become massive. We identify the spinors and vectors with partons, and, assuming the naive parton model hypothesis, we calculate the cross section e +e −→ hadrons and the structure functions of the nucleon; scaling is obtained desoite induces presence of an anomalous magnetic moment term in the coupling of the photon with the charged vector fields; the reason is that the spontaneous breaking of the symmetry indices a vector-meson dominance type of coupling between the photon and the neutral vector, which is just what is necessary to restore scaling.

S-matrix theory of the lamb shift. II

We apply the S-matrix theory and the Dashen-Frautschi technique to the Lamb shift. The formalism was developed in a first paper, in which the problem of the infrared divergence was solved and the term in α( Zα) 4Log Zα of the Lamb shift was obtained. No ultraviolet divergences appear in the calculations. In this paper, the contributions in α( Zα) 4 of the “nonrelativistic cuts”, which correspond to the “Bethe logarithm” and to the anomalous magnetic moment term, are estimated. Our approximate value of the Bethe logarithm is 3.25 for the 2 S state, and we get Δ E 2 S = 980Mc. For the anomalous magnetic moment term, analyticity assumptions lead to an exact result. Our approximate value of Δ E 2 P 1/2 is +7 Mc. By the way, we obtain the radiative corrections to the low energy Compton amplitude (for spin 0 particles) using dispersion relations.

Phenomenological description of photo-meson production

In the following we present a formula for the description of the photomesonic effect, which is essentially based on per tu rba t ion theory and which in the approximat ion m = c~ (m =nucleon mass) is in reasonable agreement with experiment, The basic idea is the recognition of the necessity to include both final state correction (in the 33-state) and anomalous magnetic momen t in teract ion into an adequate description of photomesic phenomena. We assume tha t Ko is the opera tor of photomeson product ion as determined by means of pertu rba t ion theory and including the anomalous magnetic moment term. (The anomalous magnet ic momen t is defined by pu t t ing the magnetic m o m en t # of the nucleon : / ~ ? / t ~ T 3 ; ju2 is then the anomalg~s magnet ic momen t in the sense in which we are going to use it). For the sake of comparison with the theory of CHEW and L o w [1] we consider only the lowest terms in a 1 / m expansion. ~u then mainta in tha t instead of K0 one should compare