Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 19 of 19 for “"chiral perturbation theory"”.
-
Off-shell pion electromagnetic form factors in chiral perturbation theory
… calculate the off-shell pion form factors using chiral perturbation theory, which is the effective theory for QCD at low energies. Chiral perturbation theory has previously been used to calculate the on-shell form factors. The formalism is here described, and it is modified to accomodate possible …
-
The Staggered Chiral Perturbation Theory In The Two-Flavor Case And Su(2) Chiral Analysis Of The Milc Data
… Chromodynamics: QCD) is a widely accepted theory to describe the physics of quarks and gluons. Formulating QCD on finite discrete lattices in Euclidean space-time not only enables one to study the theory non-perturbatively, but also provides a framework analogous to statistical systems, in …
-
Effective Field Theory for Doubly Heavy Baryons and Lattice QCD
… heavy baryons and lattice QCD. We construct a chiral Lagrangian for doubly heavy baryons and heavy mesons that is invariant under heavy quark-diquark symmetry at leading order and includes the leading O(1/m_Q ) symmetry violating operators. The theory is used to predict the electromagnetic …
-
Functional Renormalization Group Methods in Quantum Chromodynamics
… importance of quark effects. As in lattice gauge theory, we find that the choice of quark boundary conditions has a noticeable effect on the pion mass shift in small volumes. A comparison of our results to chiral perturbation theory and lattice QCD suggests that lattice QCD has not yet reached …
-
Determination of the Neutral B Meson and Neutral B(s) Meson Mixing Matrix Elements in 2+1 Lattice QCD
… different lattice spacings, and uses staggered chiral perturbation theory to perform the extrapolations to the physical light quark masses as well as to the continuum. All known systematic errors are explored and estimated resulting in a value and uncertainty for xi that can be used directly as …
-
Two-loop corrections to the rho-propagator in the Kroll-Lee-Zumino theory
The Abelian Kroll-Lee-Zumino theory is a renormalizable quantum field theory of charged pions and neutral rho-mesons. It provides the quantum field theory platform for the vector meson dominance model, allowing for a systematic computation of quantum corrections in perturbation theory (the ρ-π-π …
-
Measurement of the Rate of Muon Capture in Hydrogen Gas and Determination of the Proton's Pseudoscalar Coupling
… and results of modern calculations using chiral perturbation theory are quoted. The subject of union atomic and molecular kinetics in hydrogen, important for understanding many of the key features the experiment, is discussed in Chapter 3. The MuCap experimental design and apparatus are …
-
Hadronic matter: from vacuum to extreme temperature in the presence of magnetic fields
… of the Weinberg sum rules, and to determine the chiral condensates of dimension d = 6 and d = 8, and values of the chiral perturbation theory L10 and C87.
-
Electromagnetic properties of baryons from lattice QCD
… are compared with the predictions of Quenched Chiral Perturbation Theory ( Q χ PT ) and experimental values where available. Results for the charge radii and magnetic moments of the octet baryons are in accord with the predictions of the Q χ PT, suggesting that the sum of higher order terms …
-
Studies of Light Scalar Particles and Dressed Gauge Propagators in QCD
… methods. We consider here two methods, Chiral Perturbation Theory and carefully considering the poles in a scattering amplitude. In chapters 2 and 3 we apply these methods to determine the composition of the sigma(600) and f0(980) scalar resonances observed in scattering. In chapter 4 we …
-
Muon-Catalyzed Fusion Effects in the Precision Measurement of Muon Capture on the Deuteron
… through effective field theories like chiral perturbation theory. The Gamow-Teller transition in all of these processes contains a single unknown low-energy constant that determines the strength of the axial coupling to the two-nucleon system. Muon capture on the deuteron provides a …
-
Strongly coupled systems : from quantum antiferromagnets to unified models for superconductors
… numerical results that definitively confirm that chiral perturbation theory, corrected for cutoff effects in the AFHM, leads to a correct field-theoretical description of the low-temperature behavior of the spin correlation length in various spin representations S. Using a finite-size-scaling …
-
A measurement of the rate of muon capture in an ultra-pure protium gas time projection chamber
… coupling, g_P, with a precision of 6.5%. Chiral perturbation theory makes a precise calculation, g_P = 8.26 +/- 0.23, so a comparison with MuCap's experimental determination of g_P will probe our understanding of low-energy QCD and its underlying symmetries. This dissertation begins with …
-
Gravitational form factors of hadrons from lattice QCD
… fraction sum rule and the nex-to-leading order chiral perturbation theory prediction for its 𝐷-term, which is a fundamental hadron charge related to the internal forces.
-
Lattice QCD calculations of Kl3 and pion form factors using partially twisted boundary conditions
… at these simulated quark masses and then use chiral perturbation theory to extrapolate our results to physical light quark masses. We find for the charge radius of the physical pion ⟨r<sup>2</sup><sub>π</sub>⟩ = 0.418(31) fm<sup>2</sup>, in agreement with the experimentally determined result. …
-
Measurement of the Spin Structure Function GD1 of the Deuteron and Its Moments at Low Q2
… data are compared to predictions from different Chiral Perturbation Theory (χPT) calculations and phenomenological models. Extrapolations of the integrals (especially the GDH sum and the polarizability) to the real photon point (<em>Q</em><sup>2</sup>=0) enable us to test the validity of the …
-
Linear Sigma Models in QCD and S3 Symmetry for Neutrinos
… $p^2$, $p^4$ and $p^6$ seems to agree with chiral perturbation theory predictions. The model is then gauged to study the mass differences between the vector meson and the axial vector meson as a possibly useful "template" for the role of a light scalar in QCD as well as for (at a different …