5,483 research outputs found
Low energy scattering parameters from the solutions of the non-relativistic Yukawa model on a 3-dimensional lattice
The numerical solutions of the non-relativistic Yukawa model on a
3-dimensional size lattice with periodic boundary conditions are obtained. The
possibility to extract the corresponding -- infinite space -- low energy
parameters and bound state binding energies from eigensates computed at finite
lattice size is discussed
Three different approaches to the same interaction: the Yukawa model in nuclear physics
After a brief discussion of the meaning of the potential in quantum
mechanics, we examine the results of the Yukawa model (scalar meson exchange)
for the nucleon-nucleon interaction in three different dynamical frameworks:
the non-relativistic dynamics of the Schrodinger equation, the relativistic
quantum mechanics of the Bethe-Salpeter and Light-Front equations and the
lattice solution of the Quantum Field Theory, obtained in the quenched
approximation.Comment: 17 pages, 9 figures. Dedicated to Professor Henryk Witala at the
occasion of his 60th birthday. Submitted in Few-Body System
Comment on "Lattice Gluon and Ghost Propagators, and the Strong Coupling in Pure Yang-Mills Theory: Finite Lattice Spacing and Volume Effects"
The authors of ref. Phys.Rev. D94 (2016) no.1, 014502 reported about a
careful analysis of the impact of lattice artifacts on the gauge-field
propagators. In particular, they found that the low-momentum behavior of the
renormalized propagators depends on the lattice bare coupling and interpreted
this fact as the result of it being affected by finite lattice spacing
artifacts. We do not share this interpretation and present here a different and
more suitable explanation for these results
A linear acoustic model for multi-cylinder IC engine intake manifolds including the effects of the intake throttle
This paper presents a linear acoustic model of a multi-cylinder intake manifold that can be used as part of a hybrid time/frequency domain method to calculate the intake wave dynamics of practical naturally aspirated engines.
The method allows the user to construct a model of almost any manifold of complex geometry. The model is constructed as an assemblage of sub-models:
(i) A model for a straight pipe with both ends open and through-flow.
(ii) A model for an expansion chamber consisting of three lengths of pipe laid end-to-end: a narrow bore pipe expanding into a wide bore pipe contracting into a narrower bore pipe once more.
(iii) A model of a side-branch, which includes a model for a straight pipe with one end closed and a model for the three way junction that joins the side-branch to a length of flow pipe.
(iv) A model for an expansion with two (or more) side-branches, which combines the sub-models (i, ii, iii) into a multi-way (n-way) junction model.
(v) A model for an intake throttle.
Good agreement with measurement has been found for each sub-model when bench-tested in isolation and encouraging agreement has been found when many sub-models are used together to model a complex intake manifold on a running engine
Are the low-momentum gluon correlations semiclassically determined?
We argue that low-energy gluodynamics can be explained in terms of
semi-classical Yang-Mills solutions by demonstrating that lattice gluon
correlation functions fit to instanton liquid predictions for low energies and,
after cooling, in the whole range.Comment: 4 pages, revtex
Two body scattering length of Yukawa model on a lattice
The extraction of scattering parameters from Euclidean simulations of a
Yukawa model in a finite volume with periodic boundary conditions is analyzed
both in non relativistic quantum mechanics and in quantum field theory.Comment: 4 pages, talk at "18th International IUPAP conference on Few Body
Problems in Physics" (Sao Paulo, August 2006
Three-gluon vertex in Landau-gauge from quenched-lattice QCD in general kinematics
We report on a novel and extensive lattice QCD analysis for the three-gluon
vertex from quenched lattice-QCD simulations. Using standard Wilson action, we
have computed the three-gluon vertex beyond the usual kinematic restriction to
the symmetric and soft-gluon cases where it
depends on a single momentum scale. The so-dubbed bisectoral case , where the transversely projected vertex can be cast in terms of
three independent tensors, have been the object of a recent exhaustive
scrutiny, also shown in this communication. Herein, beyond this special case,
results for kinematic configurations with three different squared momenta are
also presented. All data considered, the lattice estimate of the three-gluon
vertex exhibits a clear dominance of the tree-level tensor form factor.Comment: 8 pages, 3 figures, contribution to the proceedings of the XVth Quark
confinement and the Hadron spectrum conference, August 1st - 6th, 2022,
Stavanger, Norwa
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