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Top-quark mass measurement from dilepton events at CDF II
A Abulencia1, D Acosta, J Adelman
1University of Illinois, Urbana, Illinois 61801, USA.
Physical Review Letters
|May 23, 2006
Summary
Researchers precisely measured the top-quark mass using proton-proton collisions at the Tevatron. This study provides the most accurate single measurement of the top-quark mass (M(t)) in dilepton events.
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 measurements had limitations in precision for dilepton events.
Purpose of the Study:
- To measure the top-quark mass (M(t)) using a novel matrix-element technique.
- To improve the precision of M(t) measurements in dilepton events.
- To contribute to a more accurate determination of fundamental particle physics parameters.
Main Methods:
- Analysis of tt --> bl(-)nu(l)bl'+ nu'(l) decay events from proton-proton collisions at sqrt(s) = 1.96 TeV.
- Calculation of a likelihood function for M(t) by convolving the leading-order matrix element with detector resolution functions.
- Combined analysis of 33 events with 340 pb(-1) of integrated luminosity.
Main Results:
- A single measurement of the top-quark mass M(t) = 165.2 +/- 6.1(stat) +/- 3.4(syst) GeV/c2 was obtained.
- This represents the most precise single measurement of M(t) in dilepton events to date.
- Combined with other CDF Run II measurements, M(t) = 167.9 +/- 5.2(stat) +/- 3.7(syst) GeV/c2.
Conclusions:
- The matrix-element technique is effective for precise top-quark mass measurements in dilepton events.
- The results provide a significant improvement in the precision of top-quark mass determination.
- This measurement enhances the constraints on the Standard Model and searches for new physics.
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