Compatibility and combination of world W-boson mass measurements

Abstract

AbstractThe compatibility of W-boson mass measurements performed by the ATLAS, LHCb, CDF, and D0 experiments is studied using a coherent framework with theory uncertainty correlations. The measurements are combined using a number of recent sets of parton distribution functions (PDF), and are further combined with the average value of measurements from the Large Electron–Positron collider. The considered PDF sets generally have a low compatibility with a suite of global rapidity-sensitive Drell–Yan measurements. The most compatible set is CT18 due to its larger uncertainties. A combination of all $$m_W$$ m W measurements yields a value of $$m_W = 80{,}394.6 \pm 11.5$$ m W = 80 , 394.6 ± 11.5  MeV with the CT18 set, but has a probability of compatibility of 0.5% and is therefore disfavoured. Combinations are performed removing each measurement individually, and a 91% probability of compatibility is obtained when the CDF measurement is removed. The corresponding value of the W boson mass is $$80{,}369.2 \pm 13.3$$ 80 , 369.2 ± 13.3  MeV, which differs by $$3.6\sigma $$ 3.6 σ from the CDF value determined using the same PDF set.