121311744
Polarization of recoil-electron beam in high-energy Moller and Bhabha scattering
Longitudinal and transverse polarizations of the final electron beam in Moller and Bhabha scattering are analyzed in electroweak gauge models involving more than one neutral vector boson. In pure QED, for given initial polarizations of incoming particles, the polarization of the outgoing electron beam is the same for Moller and Bhabha scattering and is energy independent. However, in various electroweak gauge models, we find that the energy dependence and final-state polarizations are in general different for the two scattering processes; thus, observing polarization effects in such scattering processes may be useful to test various gauge models at high energy.
45786266
Density matrix for polarization of high-spin particles.
The Bouchiat-Michel formula for the polarization of spin-\textonehalf{} particles is extended to higher-spin cases. Explicit formulas for massive spin-1 and spin-$\frac{3}{2}$ particles are given and discussed in connection with density matrices.
119292922
Asymptotically Static Universe
We consider a cosmology in which the final stage of the Universe is neither accelerating nor decelerating, but approaches an asymptotic state where the scale factor becomes a constant value. In order to achieve this, we first bring in a scale factor with the desired property and then determine the details of the energy contents as a result of the cosmological evolution equations. We show that such a scenario can be realized if we introduce a generalized quintom model which consists of a scalar field and a phantom with a negative cosmological constant term. The standard cold dark matter with wm = 0 is also introduced. This is possible basically due to the balance between the matter and the negative cosmological constant which tend to attract and scalar field and phantom which repel in the asymptotic region. The stability analysis shows that this asymptotic solution is classically stable.
18619603
Heavy fermion production and the symmetry breaking sector of the electroweak interactions
Abstract We point out that heavy fermion production through the fusion of the longitudinal gauge bosons might be relevant in probing the strongly interacting symmetry breaking sector of the electroweak interactions, by showing the dependence of the one loop amplitude for ( w + w − → t t ) on the symmetry breaking mechanism. The one loop amplitude for ( w + w − → t t ) is calculated for the standard model and extended technicolour theory. Techni-rho meson exchange is also briefly discussed. We find that at m t =150 GeV the cross section of top pair production in e + e − collisions is comparable in order of magnitude to that of the longitudinal gauge boson scattering.
13125480
INTERACTIONS OF A SINGLE GOLDSTINO
Abstract The single goldstino interaction is given by the goldstino derivative coupling to the supercurrent. In an alternative description, the goldstino couples nonderivatively. We give a simple method to establish the equivalence of the two approaches, valid to all orders in perturbation theory, and for any scattering process involving an arbitrary number of particles, but with a single external goldstino. In the meantime, we find in the nonderivative form of the goldstino interaction a new quartic vertex that has been overlooked, and terms that were included incorrectly in the literature. The phenomenological implication of this new quartic operator is discussed.
16964178
Borel resummation with low order perturbations in QCD
The bilocal expansion of Borel transform provides an efficient way of Borel resummation with low order perturbations in QCD. Its applications to the heavy quark pole mass, static potential, and lattice calculation are reviewed.
12710825
Coherent state quantization of SU(N) non-Abelian Chern-Simons particles
Abstract We present a new method of formulating the classical theory of SU( N + 1) non-Abelian Chern-Simons (NACS) particles for arbitrary N ⩾ 1 using the symplectic reduction of CP( N ) manifold from S 2 N +1 . Quantizing the theory using BRST formulation and coherent state path integral method, we obtain a quantum mechanical model for SU( N + 1) NACS particles.