Measurement of the W Boson Mass with the D0 Detector (1203.0293v2)

Abstract: We present a measurement of the W boson mass using data corresponding to 4.3fb^-1 of integrated luminosity collected with the D0 detector during Run II at the Fermilab Tevatron p\bar{p} collider. With a sample of 1,677,394 W -> e\nu candidate events, we measure M_W = 80.367 +/- 0.026 GeV. This result is combined with an earlier D0 result determined using an independent Run II data sample, corresponding to 1fb^-1 of integrated luminosity, to yield M_W = 80.375 +/- 0.023 GeV.

Measurement of the W Boson Mass with the D0 Detector

The paper provides an extensive paper focused on the precision measurement of the W boson mass, a fundamental parameter within the electroweak sector of the Standard Model (SM). Conducted using data collected from the Fermilab Tevatron's D0 detector during Run II, the analysis emphasizes high-level methodological approaches to refine the measurement precision of $M_W$. The mass of the W boson, coupled with other observables such as the top quark mass, plays a pivotal role in constraining the SM Higgs boson mass. Accurate measurement of these parameters is critical to ongoing validations of the SM and carries significant implications for future theoretical developments in particle physics.

Data Collection and Methodology

The research utilizes a substantial dataset corresponding to an integrated luminosity of 4.3 fb${}^{-1}$, including 1,677,394 W boson decay events identified as W → eν. Leveraging the D0 detector's capabilities, particularly its precision in electron energy measurements, the paper employs three perpendicular kinematic variables—transverse mass ($m_T$), electron transverse momentum ($p_T^e$), and neutrino transverse momentum ($p_T^\nu$). The detection mechanisms are accentuated by a systematic model addressing detector response functions and a variety of corrections to confront the consequences of increased instantaneous luminosity.

Results

The paper reports a new measurement of the W boson mass as $M_W = 80.367 \pm 0.026$ GeV. This was achieved by combining data from both transverse mass and transverse momentum observations, each carrying its fit range and statistical rigor. Comparisons with prior D0 measurements and other world averages such as the top quark mass illustrate a consistent alignment within the expected theoretical frameworks of the SM.

Uncertainty and Systematics

Systematic uncertainties are meticulously categorized into experimental and production sources. The dominant contributions include the electron energy calibration, electron resolution model, and hadronic recoil model—many derived from the control samples of Z → ee events used to calibrate the response systems. Production mechanism uncertainties largely involve parton distribution functions and QCD corrections, which are constrained with parametrized Monte Carlo simulations (MC).

Implications and Future Prospects

The findings solidify precision measurements essential for validating SM predictions about the Higgs boson mass. With the meticulous reduction of systematic and statistical uncertainties, this paper approaches an ideal framework for confronting theoretical expectations in both current and emerging particle physics models. The future potential of further analysis using the complete D0 dataset promises the refinement of $M_W$ precision, strengthening or challenging current theoretical paradigms within the field.

Conclusion

The intricate methodologies and thorough data-handling practices outlined in this paper advance the accuracy of W boson mass measurements, reinforcing the physical integrity of the SM and providing groundwork for hypothesis testing beyond the existing theoretical universe. As experimental accuracy continues to improve, such results will enable deeper penetration into the fabric of particle physics, possibly hinting at new phenomena or reaffirming present knowledge.