Definition of electromagnetic local spatial densities for composite spin- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mn>1</mml:mn><mml:mo stretchy="false">/</mml:mo><mml:mn>2</mml:mn></mml:math> systems

Relativistic Extension of the Electromagnetic Current for Composite Systems

Electromagnetic Properties for Arbitrary Spin Particles: Part 2 − Natural Moments and Transverse Charge Densities

In a set of two papers, we propose to study an old-standing problem, namely the electromagnetic interaction for particles of arbitrary spin. Based on the assumption that light-cone helicity at tree level and Q = 0 should be conserved non-trivially by the electromagnetic interaction, we are able to derive all the natural electromagnetic moments for a pointlike particle of any spin. In this secon...

The Electromagnetic Interactions of Loosely Bound Composite Systems ?

Contrary to popular assumption, the interaction of a composite system with an external electromagnetic field is not equal to the sum of the individual Foldy-Wouthuysen interactions of. the constituents if -the constituents have spin. We give the correct interaction, and note that it is consistent with the DrellHearn-Gerasimov sum rule and the low energy theorem for Compton scattering. We also d...

A Definition of various densities and functions

A Dirichlet, with variables π = {π 1 ,. .. , π Ω } and parameters λ = {λ 1 ,. .. , λ Ω }: D(π|λ) = Γ(Ω ω=1 λ ω) Ω ω=1 Γ(λ ω) Ω ω=1 π λω−1 ω (1) where π 1 ,. .. , π Ω ≥ 0 and λ 1 ,. .. , λ Ω > 0 and Ω ω=1 π ω = 1. The Dirichlet distribution is the conjugate to the multinomial density. A symmetric Dirichlet density has all the λ's the same value, e.g. λ 0 , and the density reduces to:

Universal properties of the electromagnetic interactions of spin-one systems.

The dominance of helicity-conserving amplitudes in gauge theory is shown imply universal ratios for the charge, magnetic, and quadrupole form factors spin-one bound states: Gc(Q2) : GM(Q2) : GQ(Q2) = (1 $7) : 2 : -1. These ratios hold at large space-like or time-like momentum transfer in the case of composite systems such as the p or deuteron in &CD. They are also the ratios predicted’for the e...