Measurement of the W Boson Mass with the D0 Detector

Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters (Impact Factor: 7.51). 04/2012; 108(15):151804. DOI: 10.1103/PhysRevD.89.012005
Source: PubMed


We give a detailed description of the measurement of the W boson mass, MW, performed on an integrated luminosity of 4.3 fb-1, which is based on similar techniques as used for our previous measurement done on an independent data set of 1 fb-1 of data. The data were collected using the D0 detector at the Fermilab Tevatron Collider. This data set yields 1.68×106 W→eν candidate events. We measure the mass using the transverse mass, electron transverse momentum, and missing transverse energy distributions. The MW measurements using the transverse mass and the electron transverse momentum distributions are the most precise of these three and are combined to give MW=80.367±0. 013(stat)±0.022(syst) GeV=80.367±0.026 GeV. When combined with our earlier measurement on 1 fb-1 of data, we obtain MW=80.375±0.023 GeV.

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    ABSTRACT: The latest measurements of the mass of the W boson, one of two elementary particles that mediate the weak nuclear force, are a powerful reminder of the profound beauty in the standard model of particle physics.
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    ABSTRACT: The W mass is a crucial parameter in the Standard Model (SM) of particle physics, providing constraints on the mass of the Higgs boson as well as on new physics models via quantum loop corrections. On the other hand, any deviation of the triple gauge boson couplings (TGC) from their values predicted by the SM would be also an indication for new physics. We present recent measurements on W boson mass and searches for anomalous TGC (aTGC) in Wγ, Zγ, WW, WZ and ZZ at Fermilab Tevatron both by CDF and DØ Collaborations. The CDF Collaboration has measured the W boson mass using data corresponding to 2.2 fb-1 of integrated luminosity. The measurement, performed using electron and muon decays of W boson, yields a mass of MW = 80387 ± 19 MeV. The DØ Collaboration has measured MW = 80367 ± 26 MeV with data corresponding to 4.3 fb-1 of integrated luminosity in the channel W → ev. The combination with an earlier DØ result, using independant data sample at 1 fb-1 of integrated luminosity, yields MW = 80375 ± 23 MeV. The limits on anomalous TGCs parameters are consistent with the SM expectations.
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