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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Light gluino, light bottom squark scenario, and LEP predictions
Kingman Cheung1, Wai-Yee Keung
1National Center for Theoretical Sciences, National Tsing Hua University, Hsinchu, Taiwan, Republic of China. cheung@phys.cts.nthu.edu.tw
Physical Review Letters
|December 18, 2002
Summary
A proposed scenario involving light gluinos and sbottoms cannot be constrained by current Large Electron-Positron Collider (LEP) data. However, future experiments at the Large Electron-Positron Collider II (LEPII) may detect an excess of four-bottom events, supporting this theory.
Area of Science:
- Particle Physics
- High-Energy Physics
- Beyond Standard Model Physics
Background:
- Discrepancies in b quark production at the Tevatron suggest new physics.
- A scenario with light gluinos and sbottoms was proposed to explain these observations.
Purpose of the Study:
- To investigate the model-independent predictions of the light gluino/sbottom scenario.
- To assess the potential of Z boson decays and electron-positron collisions to constrain this scenario.
Main Methods:
- Analysis of Z boson decays (Z-->qqgg) at the Z0 pole.
- Examination of electron-positron collisions (e(+)e(-)-->qqgg) at LEPII.
- Comparison of theoretical predictions with experimental data from LEP I and projections for LEPII.
Main Results:
- LEP I data for Z-->qqg*-->qqbb decays are insufficient to constrain the light gluino/sbottom scenario due to large uncertainties.
- The predicted ratio of qqgg to qqbb events at LEPII is significant (0.4-0.2).
Conclusions:
- LEP I experiments cannot rule out the light gluino/sbottom scenario.
- LEPII has the potential to observe an excess in four-bottom events, providing evidence for this scenario.
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