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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 × 10 6 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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We present a search for a narrow resonance in the inclusive diphoton final state using ∼ 2.7 fb −1 of data collected with the D0 detector at the Fermilab Tevatron pp Collider. We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.

We summarize and combine direct measurements of the mass of the W boson in √ s = 1.96 TeV proton-antiproton collision data collected by CDF and D0 experiments at the Fermilab Tevatron Collider. Earlier measurements from CDF and D0 are combined with the two latest, more precise measurements: a CDF measurement in the electron and muon channels using data corresponding to 2.2 fb −1 of integrated luminosity, and a D0 measurement in the electron channel using data corresponding to 4.3 fb −1 of integrated luminosity. The resulting Tevatron average for the mass of the W boson is MW = 80 387 ± 16 MeV. Including measurements obtained in electron-positron collisions at LEP yields the most precise value of MW = 80 385 ± 15 MeV.

We report a measurement of the mass of the top quark in lepton+jets final states of pp →tt data corresponding to 2.6 fb −1 of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider. A matrix-element method is developed that combines an in situ jet energy calibration with our standard jet energy scale derived from studies of γ+jet and dijet events. We then implement a flavor-dependent jet response correction through a novel approach. This method is used to measure a top-quark mass of mt = 176.01 ± 1.64 GeV. Combining this result with our previous result obtained on an independent data set, we measure a top-quark mass of mt = 174.94 ± 1.49 GeV for a total integrated luminosity of 3.6 fb −1 .

We present a measurement of forward-backward asymmetry in top quark-antiquark production in proton-antiproton collisions in the final state containing a lepton and at least four jets. Using a dataset corresponding to an integrated luminosity of 5.4 fb −1 , collected by the D0 experiment at the Fermilab Tevatron Collider, we measure the tt forward-backward asymmetry to be (9.2 ± 3.7)% at the reconstruction level. When corrected for detector acceptance and resolution, the asymmetry is found to be (19.6 ± 6.5)%. We also measure a corrected asymmetry based on the lepton from a top quark decay, found to be (15.2 ± 4.0)%. The results are compared to predictions based on the next-to-leading-order QCD generator mc@nlo. The sensitivity of the measured and predicted asymmetries to the modeling of gluon radiation is discussed.

Obtaining atomic level information about the structure and dynamics of biomolecules is critical to understand their function. Nuclear magnetic resonance (NMR) spectroscopy provides unique insights into the dynamic nature of biomolecules and their interactions, capturing transient conformers and their features. However, relaxation-induced line broadening and signal overlap make it challenging to apply NMR to large biological systems. Here, we take advantage of the high sensitivity and the broad chemical-shift range of 19 F nuclei, and leverage the remarkable relaxation properties of the aromatic 19 F- 13 C spin pair to disperse 19 F resonances in a 2-dimensional transverse relaxation optimized TROSY spectrum. We demonstrate the application of the 19 F- 13 C TROSY to investigate proteins and nucleic acids. This experiment expands the scope of 19 F NMR in the study of structure, dynamics and function of large and complex biological systems and provides a powerful background-free NMR probe.