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Upper bound on the hadronic light-by-light contribution to the muon g - 2
Jens Erler1, Genaro Toledo Sánchez
1Instituto de Física, Universidad Nacional Autónoma de México, Mexico DF, Mexico.
Physical Review Letters
|December 13, 2006
Summary
This study estimates the hadronic light-by-light contribution to the muon
Area of Science:
- Particle Physics
- Quantum Field Theory
- Electroweak Interactions
Background:
- Electroweak observables are influenced by hadronic loops.
- Parton-level effects may significantly saturate these contributions.
Purpose of the Study:
- To provide a parton-level estimate for the hadronic light-by-light contribution to the anomalous magnetic moment of the muon.
- To develop a transparent error estimation for this contribution.
Main Methods:
- A genuine parton-level estimation approach was employed.
- Detailed quark mass definitions and values were utilized.
- An interpolation method was used to establish an upper bound.
Main Results:
- The hadronic light-by-light contribution to the anomalous magnetic moment of the muon, a(LBL)/(mu)(had), was estimated.
- An upper bound was determined: a(LBL)/(mu)(had) < 1.59x10^-9 (95% C.L.).
Conclusions:
- The parton-level approach offers a viable method for estimating hadronic contributions.
- The derived upper bound provides a constraint for theoretical and experimental comparisons.
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