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Published on: November 16, 2013
Cross-section-constrained top-quark mass measurement from dilepton events at the Tevatron
T Aaltonen1, J Adelman, T Akimoto
1Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland.
Physical Review Letters
|March 21, 2008
Summary
This study presents the first top-quark mass measurement incorporating a cross-section constraint. The new method yields a precise top-quark mass value of 170.7 GeV/c², improving upon previous determinations.
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 testing the Standard Model of particle physics.
- Previous top-quark mass measurements have uncertainties stemming from various sources.
Purpose of the Study:
- To report the first top-quark mass measurement utilizing a cross-section constraint for improved accuracy.
- To present a new method for determining the top-quark mass at the Tevatron.
Main Methods:
- Utilized a dilepton top-antitop (tt) event candidate sample.
- Collected data using the Collider Detector II at Fermilab.
- Applied a cross-section constraint to refine the mass determination.
Main Results:
- Measured a top-quark mass of 170.7 (stat) +4.2 (syst) +2.4 (theory) GeV/c² with the cross-section constraint.
- The measurement without the constraint yielded 169.7 (stat) +5.2 (syst) GeV/c².
- The integrated luminosity of the data sample was 1.2 fb⁻¹.
Conclusions:
- The cross-section constraint method provides a more precise top-quark mass measurement.
- This result contributes to a better understanding of the top quark properties and the Standard Model.
- Further refinement of top-quark mass measurements is essential for future physics explorations.
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