The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, M W , using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera–electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain M W = 80 , 433.5 ± 6.4 stat ± 6.9 syst = 80 , 433.5 ± 9.4  MeV / c 2 , the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega–electron volts; c , speed of light in a vacuum). This measurement is in significant tension with the standard model expectation.

In this paper, we present the analysis and results of a direct measurement of the cosmic-ray proton spectrum with the CALET instrument onboard the International Space Station, including the detailed assessment of systematic uncertainties. The observation period used in this analysis is from October 13, 2015 to August 31, 2018 (1054 days). We have achieved the very wide energy range necessary to carry out measurements of the spectrum from 50 GeV to 10 TeV covering, for the first time in space, with a single instrument the whole energy interval previously investigated in most cases in separate subranges by magnetic spectrometers (BESS-TeV, PAMELA, and AMS-02) and calorimetric instruments (ATIC, CREAM, and NUCLEON). The observed spectrum is consistent with AMS-02 but extends to nearly an order of magnitude higher energy, showing a very smooth transition of the power-law spectral index from −2.81 AE 0.03 (50-500 GeV) neglecting solar modulation effects (or −2.87 AE 0.06 including solar modulation effects in the lower energy region) to −2.56 AE 0.04 (1-10 TeV), thereby confirming the existence of spectral hardening and providing evidence of a deviation from a single power law by more than 3σ.

We present a measurement of the ratio of the top-quark branching fractions R = B(t → W b)/B(t → W q), where q represents quarks of type b, s, or d, in the final state with a lepton and hadronic jets. The measurement uses √ s = 1.96 TeV proton-antiproton collision data from 8.7 fb −1 of integrated luminosity collected with the Collider Detector at Fermilab during Run II of the Tevatron. We simultaneously measure R = 0.94±0.09 (stat+syst) and the tt production cross section σ tt = 7.5±1.0 (stat+syst) pb. The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element, |V tb | = 0.97 ± 0.05 (stat+syst) is extracted assuming three generations of quarks, and a lower limit of |V tb | > 0.89 at 95% credibility level is set.PACS numbers: 12.15. Hh, 13.85.Qk, 14.65.Ha In the standard model (SM) the top-quark decay rate into a W boson and a down-type quark q (q = d, s, b) is proportional to |V tq | 2 , the squared magnitude of the element of the Cabibbo-Kobayashi-Maskawa (CKM) ma- * Deceased † With visitors from

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