Four quark operators for kaon bag parameter with gradient flow
| Autor: | Kazuyuki Kanaya, Yusuke Taniguchi, Hiroshi Suzuki, Asobu Suzuki |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Physics
Quark Quantum chromodynamics 010308 nuclear & particles physics High Energy Physics::Lattice High Energy Physics - Lattice (hep-lat) Nuclear Theory High Energy Physics::Phenomenology FOS: Physical sciences Observable Lattice QCD 01 natural sciences Renormalization symbols.namesake High Energy Physics - Lattice Lattice (order) 0103 physical sciences Homogeneous space symbols Feynman diagram High Energy Physics::Experiment 010306 general physics Mathematical physics |
| Zdroj: | Physical Review |
| Popis: | To study the CP-violation using the $K_0-\bar{K}_0$ oscillation, we need the kaon bag parameter which represents QCD corrections in the leading Feynman diagrams. The lattice QCD provides us with the only way to evaluate the kaon bag parameter directly from the first principles of QCD. However, a calculation of relevant four quark operators with theoretically sound Wilson-type lattice quarks had to carry a numerically big burden of extra renormalizations and resolution of extra mixings due to the explicit chiral violation. Recently, the Small Flow-time eXpansion (SFtX) method was proposed as a general method based on the gradient flow to correctly calculate any renormalized observables on the lattice, irrespective of the explicit violations of related symmetries on the lattice. To apply the SFtX method, we need matching coefficients, which relate finite operators at small flow-times in the gradient flow scheme to renormalized observables in conventional renormalization schemes. In this paper, we calculate the matching coefficients for four quark operators and quark bi-linear operators, relevant to the kaon bag parameter. 23 pages, 3 figures. Published version: a discussion in the introduction supplemented, typos corrected, figures replaced by their vector (pdf) versions, results and conclusions not changed |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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