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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
First search for multijet resonances in sqrt(s) = 1.96 TeV pp collisions
T Aaltonen1, B Álvarez González, S Amerio
1Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland.
Physical Review Letters
|August 27, 2011
Summary
This study searched for new physics in three-jet events at the Fermilab Tevatron, analyzing multijet collisions. No significant excess was found, setting limits on supersymmetric particle production.
Area of Science:
- High Energy Physics
- Particle Physics
- Collider Physics
Background:
- Multijet events are a significant background in particle physics searches.
- Supersymmetric (SUSY) models predict new particles like gluinos and squarks.
- R-parity violating decays offer a specific signature for new physics detection.
Purpose of the Study:
- To perform the first model-independent search for three-jet hadronic resonances.
- To set limits on the pair production of supersymmetric gluinos and squarks with specific decay channels.
- To establish a benchmark for new physics searches using multijet signatures.
Main Methods:
- Analysis of proton-antiproton collisions at sqrt(s) = 1.96 TeV using the CDF II detector.
- Development of selection criteria based on kinematic properties of jet combinations.
- Utilizing an integrated luminosity of 3.2 fb⁻¹ for data analysis.
Main Results:
- No significant excess of events was observed outside the top quark mass window.
- 95% confidence level limits were placed on the production cross section for specific supersymmetric particle production and decay scenarios.
- Limits were set as a function of gluino mass, ranging from 77 GeV/c² to 240 GeV/c².
Conclusions:
- The search for three-jet hadronic resonances yielded no evidence for new physics beyond the Standard Model in the analyzed data.
- The results constrain specific scenarios of supersymmetric particle production and decay.
- This study demonstrates the utility of multijet events for model-independent searches.
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