Systematic effects of the quenched approximation on the strong penguin contribution to {epsilon}{sup '}/{epsilon}

Journal Article · Tue Aug 01 04:00:00 EDT 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.74.034510· OSTI ID:20869269

Aubin, C; Christ, N H; Li, S ^[1]; Dawson, C; Noaki, J ^[2]; Laiho, J W ^[3]; Soni, A ^[3]

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1. Physics Department, Columbia University, New York, New York 10027 (United States)
2. RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States)
3. Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

We discuss the implementation and properties of the quenched approximation in the calculation of the left-right, strong penguin contributions (i.e. Q{sub 6}) to {epsilon}{sup '}/{epsilon}. The coefficient of the new chiral logarithm, discovered by Golterman and Pallante, which appears at leading order in quenched chiral perturbation theory is evaluated using both the method proposed by those authors and by an improved approach which is free of power divergent corrections. The result implies a large quenching artifact in the contribution of Q{sub 6} to {epsilon}{sup '}/{epsilon}. This failure of the quenched approximation affects only the strong penguin operators and so does not affect the Q{sub 8} contribution to {epsilon}{sup '}/{epsilon} nor ReA{sub 0}, ReA{sub 2} and thus, the {delta}I=1/2 rule at tree level in chiral perturbation theory.

• OSTI ID: 20869269
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 3 Vol. 74; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
APPROXIMATIONS
CHIRALITY
CORRECTIONS
FEYNMAN DIAGRAM
FIELD OPERATORS
PERTURBATION THEORY
QUENCHING