Strangeness And Charge Symmetry Violation In Nucleon Structure (springer Theses)
by Phiala Elisabeth Shanahan /
2016 / English / PDF
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This thesis discusses two key topics: strangeness and charge
symmetry violation (CSV) in the nucleon. It also provides a
pedagogical introduction to chiral effective field theory
tailored to the high-precision era of lattice quantum
chromodynamics (QCD). Because the nucleon has zero net
strangeness, strange observables give tremendous insight into the
nature of the vacuum; they can only arise through quantum
fluctuations in which strange–antistrange quark pairs are
generated. As a result, the precise values of these quantities
within QCD are important in physics arenas as diverse as
precision tests of QCD, searches for physics beyond the Standard
Model, and the interpretation of dark matter direct-detection
experiments. Similarly, the precise knowledge of CSV observables
has, with increasing experimental precision, become essential to
the interpretation of many searches for physics beyond the
Standard Model. In this thesis, the numerical lattice gauge
theory approach to QCD is combined with the chiral perturbation
theory formalism to determine strange and CSV quantities in a
diverse range of observables including the octet baryon masses,
sigma terms, electromagnetic form factors, and parton
distribution functions. This thesis builds a comprehensive and
coherent picture of the current status of understanding of
strangeness and charge symmetry violation in the nucleon.
This thesis discusses two key topics: strangeness and charge
symmetry violation (CSV) in the nucleon. It also provides a
pedagogical introduction to chiral effective field theory
tailored to the high-precision era of lattice quantum
chromodynamics (QCD). Because the nucleon has zero net
strangeness, strange observables give tremendous insight into the
nature of the vacuum; they can only arise through quantum
fluctuations in which strange–antistrange quark pairs are
generated. As a result, the precise values of these quantities
within QCD are important in physics arenas as diverse as
precision tests of QCD, searches for physics beyond the Standard
Model, and the interpretation of dark matter direct-detection
experiments. Similarly, the precise knowledge of CSV observables
has, with increasing experimental precision, become essential to
the interpretation of many searches for physics beyond the
Standard Model. In this thesis, the numerical lattice gauge
theory approach to QCD is combined with the chiral perturbation
theory formalism to determine strange and CSV quantities in a
diverse range of observables including the octet baryon masses,
sigma terms, electromagnetic form factors, and parton
distribution functions. This thesis builds a comprehensive and
coherent picture of the current status of understanding of
strangeness and charge symmetry violation in the nucleon.