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Baryonic Z' explanation for the CDF Wjj excess
Kingman Cheung1, Jeonghyeon Song
1Division of Quantum Phases & Devices, School of Physics, Konkuk University, Seoul 143-701, Republic of Korea.
Physical Review Letters
|June 25, 2011
Summary
A new baryonic Z' boson model explains the CDF anomaly in dijet events. This model, consistent with UA2 and LEP data, predicts observable signatures at the Tevatron, including Z' production via W or photon fusion.
Area of Science:
- High Energy Physics
- Particle Physics
- Collider Physics
Background:
- The Collider Detector at Fermilab (CDF) observed an excess of dijet events within a specific invariant mass window (120-160 GeV) when produced alongside a W boson.
- This anomaly suggests the potential existence of new physics beyond the Standard Model of particle physics.
Purpose of the Study:
- To investigate a baryonic Z' model as a potential explanation for the observed CDF dijet anomaly.
- To assess the constraints on this Z' model from existing experimental data and explore its implications for future collider experiments.
Main Methods:
- The study employs theoretical analysis of a baryonic Z' model with negligible couplings to leptons.
- It evaluates constraints from UA2 dijet data and Large Electron-Positron Collider (LEP) precision measurements.
- The model's predictions for Tevatron collider signatures are calculated.
Main Results:
- The baryonic Z' model successfully explains the CDF dijet anomaly in the 120-160 GeV mass window.
- The model is consistent with constraints from UA2 dijet data and LEP measurements.
- A cross-section of approximately 4 pb for WZ' production is predicted, aligning with observations.
Conclusions:
- The proposed baryonic Z' model offers a viable explanation for the CDF anomaly.
- Future Tevatron experiments could probe this model by searching for associated production channels like γZ'→γjj and ZZ'→ℓ(+)ℓ(-) jj.
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