37,640 research outputs found
Magnetic moment of the Roper resonance
The magnetic moment of the Roper resonance is calculated in the framework of
a low-energy effective field theory of the strong interactions. A systematic
power-counting procedure is implemented by applying the complex-mass scheme.Comment: 13 pages, 4 figure
Electromagnetic form factors of the nucleon in effective field theory
We calculate the electromagnetic form factors of the nucleon to third chiral
order in manifestly Lorentz-invariant effective field theory. The rho and omega
mesons as well as the Delta(1232) resonance are included as explicit dynamical
degrees of freedom. To obtain a self-consistent theory with respect to
constraints we consider the proper relations among the couplings of the
effective Lagrangian. For the purpose of generating a systematic power
counting, the extended on-mass-shell renormalization scheme is applied in
combination with the small-scale expansion. The results for the electric and
magnetic Sachs form factors are analyzed in terms of experimental data and
compared to previous findings in the framework of chiral perturbation theory.
The pion-mass dependence of the form factors is briefly discussed.Comment: 26 pages, 9 figure
Analytical studies of in-reactor tests of a nuclear light bulb unit cell
Analytical studies of in-reactor tests of nuclear light bulb unit cell using Pewee, nuclear furnace, and high flux isotope reactor
Complex-mass scheme and perturbative unitarity
We derive cutting rules for loop integrals containing propagators with
complex masses. Using a field-theoretical model of a heavy vector boson
interacting with a light fermion, we demonstrate that the complex-mass scheme
respects unitarity order by order in a perturbative expansion provided that the
renormalized coupling constant remains real.Comment: Accepted for publication in International Journal of Modern Physics
Analytical studies of nuclear light bulb engine radiant heat transfer and performance characteristics
Analytical model of nuclear light bulb engine radiant heat transfer and engine performance, dynamics and control, heat loads and shutdown characteristic
Complex-mass scheme and resonances in EFT
The complex-mass scheme (CMS) provides a consistent framework for dealing
with unstable particles in quantum field theory and has been successfully
applied to various loop calculations. As applications of the CMS in chiral
effective field theory we consider the form factor of the pion in the time-like
region and the magnetic moment of the Roper resonance.Comment: 4 pages, 2 figures, contribution to the workshop NSTAR 201
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