101 research outputs found
Factorization effects in a model of unstable particles
The effects of factorization are considered within the framework of the model
of unstable particles with a smeared mass. It is shown that two-particle cross
section and three-particle decay width can be described by the universal
factorized formulae for an unstable particles of an arbitrary spin in an
intermediate state. The exact factorization is caused by the specific structure
of the model unstable-particle propagators. This result is generalized to
complicated scattering and decay-chain processes with unstable particles in
intermediate states. We analyze applicability of the method and evaluate its
accuracy.Comment: 13 pages, 7 figure
N=4 supersymmetric mechanics with nonlinear chiral supermultiplet
We construct N=4 supersymmetric mechanics using the N=4 nonlinear chiral
supermultiplet. The two bosonic degrees of freedom of this supermultiplet
parameterize the sphere S(2) and go into the bosonic components of the standard
chiral multiplet when the radius of the sphere goes to infinity. We construct
the most general action and demonstrate that the nonlinearity of the
supermultiplet results in the deformation of the connection, which couples the
fermionic degrees of freedom with the background, and of the bosonic potential.
Also a non-zero magnetic field could appear in the system.Comment: 5 page
Generalized N = 2 Super Landau Models
We generalize previous results for the superplane Landau model to exhibit an
explicit worldline N = 2 supersymmetry for an arbitrary magnetic field on any
two-dimensional manifold. Starting from an off-shell N = 2 superfield
formalism, we discuss the quantization procedure in the general case
characterized by two independent potentials on the manifold and show that the
relevant Hamiltonians are factorizable. In the restricted case when both the
Gauss curvature and the magnetic field are constant over the manifold and, as a
consequence, the underlying potentials are related, the Hamiltonians admit
infinite series of factorization chains implying the integrability of the
associated systems. We explicitly determine the spectrum and eigenvectors for
the particular model with CP^1 as the bosonic manifold.Comment: 26 page
Diagonalization of the neutralino mass matrix and boson-neutralino interaction
We analyze a connection between neutralino mass sign, parity and structure of
the neutralino-boson interaction. Correct calculation of spin-dependent and
spin-independent contributions to neutralino-nuclear scattering should consider
this connection. A convenient diagonalization procedure, based on the
exponetial parametrization of unitary matrix, is suggested.Comment: 21 pages, RevTex
Supersymmetric Quantum Hall Liquid with a Deformed Supersymmetry
We construct a supersymmetric quantum Hall liquid with a deformed
supersymmetry. One parameter is introduced in the supersymmetric Laughlin
wavefunction to realize the original Laughlin wavefunction and the Moore-Read
wavefunction in two extremal limits of the parameter. The introduced parameter
corresponds to the coherence factor in the BCS theory. It is pointed out that
the parameter-dependent supersymmetric Laughlin wavefunction enjoys a deformed
supersymmetry. Based on the deformed supersymmetry, we construct a
pseudo-potential Hamiltonian whose groundstate is exactly the
parameter-dependent supersymmetric Laughlin wavefunction. Though the SUSY
pseudo-potential Hamiltonian is parameter-dependent and non-Hermitian, its
eigenvalues are parameter-independent and real.Comment: 14 pages, contribution to the proceedings of the Group 27 conference,
Yerevan, Armenia, August 13-19, 2008, published versio
Strong Couplings of Heavy Mesons to A Light Vector Meson in QCD
We make a detailed analysis of the and
strong couplings and
using QCD light cone sum rules(LCSR). The
existing some negligence is pointed out in the previous LCSR calculation on
) and an updated estimate is presented. Our
findings can be used to understand the behavior of the
semileptonic form factors at large momentum transitions.Comment: 15 pages, latex, 2 figures, version appearing in PRD, typos correcte
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