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Full-Text Articles in Physics
The Pion Form Factor And Momentum And Angular Momentum Fractions Of The Proton In Lattice Qcd, Gen Wang
The Pion Form Factor And Momentum And Angular Momentum Fractions Of The Proton In Lattice Qcd, Gen Wang
Theses and Dissertations--Physics and Astronomy
Lattice Quantum Chromodynamics (QCD) provides a way to have a precise calculation and a new way of understanding the hadrons from first principles. From this perspective, this dissertation focuses first on a precise calculation of the pion form factor using overlap fermions on six ensembles of 2+1-flavor domain-wall configurations generated by the RBC/UKQCD collaboration with pion masses varying from 137 to 339 MeV. Taking advantage of the fast Fourier transform, low-mode substitution (LMS) and the multi-mass algorithm to access many combinations of source and sink momenta, we have done a simulation with various valence quark masses and with a range …
Disconnected-Sea Quarks Contribution To Nucleon Electromagnetic Form Factors, Raza Sabbir Sufian
Disconnected-Sea Quarks Contribution To Nucleon Electromagnetic Form Factors, Raza Sabbir Sufian
Theses and Dissertations--Physics and Astronomy
We present comprehensive analysis of the light and strange disconnected-sea quarks contribution to the nucleon electric and magnetic form factors. The lattice QCD estimates of strange quark magnetic moment GsM (0) = −0.064(14)(09) μN and the mean squared charge radius ⟨r2s⟩E = −0.0043(16)(14) fm2 are more precise than any existing experimental measurements and other lattice calculations. The lattice QCD calculation includes ensembles across several lattice volumes and lattice spacings with one of the ensembles at the physical pion mass. We have performed a simultaneous chiral, infinite volume, and continuum extrapolation in …
Lattice Qcd Calculation Of The Momentum Fraction Carried By Quarks In The Nucleon, And The Roper Puzzle, Mingyang Sun
Lattice Qcd Calculation Of The Momentum Fraction Carried By Quarks In The Nucleon, And The Roper Puzzle, Mingyang Sun
Theses and Dissertations--Physics and Astronomy
This thesis is concerned with the lattice QCD calculation of the momentum fraction carried by quarks in the nucleon. Particularly, the strange quark contribution, (x)s, is calculated, as well as the ratio of the strange (x) to that of u/d in the disconnected insertion which will be useful in constraining the global fit of parton distribution functions at small x. The disconnected insertion is known to be hard to calculate on the lattice. We adopt the overlap fermion action on several 2 + 1 flavor domain-wall fermion ensembles with a light sea quark mass which corresponds to pion …