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Measurement of the W boson mass
V M Abazov1, B Abbott, M Abolins
1Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters
|November 13, 2009
Summary
The D0 experiment measured the W boson mass using electron neutrino decays, achieving the most precise single-experiment value to date. This precise W boson mass measurement refines our understanding of the Standard Model.
Area of Science:
- Particle Physics
- High Energy Physics
- Electroweak Interactions
Background:
- The W boson is a fundamental particle mediating the weak nuclear force.
- Precise measurements of the W boson mass are crucial for testing the Standard Model of particle physics.
- Previous measurements have provided constraints on the W boson mass, but further precision is desired.
Purpose of the Study:
- To present a new, highly precise measurement of the W boson mass.
- To utilize a large dataset from the Fermilab Tevatron collider for improved accuracy.
- To contribute to the ongoing effort of testing the Standard Model with precise electroweak measurements.
Main Methods:
- Analysis of W boson decays to electron and neutrino (W-->e(nu)) using data from the D0 detector.
- Selection of a large sample of candidate W-->e(nu) events (499,830 events).
- Statistical and systematic uncertainty evaluation for the W boson mass determination.
Main Results:
- A measurement of the W boson mass (M(W)) of 80.401 +/- 0.043 GeV.
- This result represents the most precise measurement of the W boson mass obtained from a single experiment.
- The achieved precision allows for stringent tests of theoretical predictions.
Conclusions:
- The measurement provides a significant contribution to the world average W boson mass.
- The high precision achieved validates the experimental techniques and data analysis.
- This result further constrains parameters within the Standard Model and may hint at new physics beyond it.
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