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Updated: May 17, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Precision top-quark mass measurement at CDF.
T Aaltonen1, B Alvarez González, S Amerio
1Division of High Energy Physics, Department of Physics, University of Helsinki, Helsinki, Finland.
Physical Review Letters
|October 30, 2012
Summary
This study reports the most precise measurement of the top-quark mass at 172.85 ± 0.98 GeV/c². The analysis utilized the full Tevatron dataset from the CDF II detector in proton-antiproton collisions.
Area of Science:
- High Energy Physics
- Particle Physics
- Collider Physics
Background:
- The top quark is the heaviest known elementary particle.
- Precise measurements of the top-quark mass are crucial for understanding the Standard Model of particle physics and searching for new physics.
- Previous measurements have established its mass but with room for improved precision.
Purpose of the Study:
- To perform a precision measurement of the top-quark mass.
- To leverage the full dataset collected by the CDF II detector at the Tevatron.
- To achieve the single most precise determination of the top-quark mass to date.
Main Methods:
- Analysis of tt¯ candidate events in the lepton+jets decay channel.
- Utilizing a full sample of Tevatron proton-antiproton collisions (8.7 fb⁻¹).
- Employing template-based likelihood fits with in situ jet energy scale calibration.
Main Results:
- The top-quark mass was measured to be M(top) = 172.85 ± 0.71 (stat) ± 0.85 (syst) GeV/c².
- This result represents the single most precise measurement of the top-quark mass.
- The analysis included a detailed study of signal and background event distributions.
Conclusions:
- The achieved precision advances our understanding of the top quark's properties.
- This measurement provides a stringent test of the Standard Model.
- Further studies can build upon this precise value for future theoretical and experimental investigations.
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