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  1. We present a new measurement of the positive muon magnetic anomaly, ๐‘Ž๐œ‡โ‰ก(๐‘”๐œ‡โˆ’2)/2, from the Fermilab Muon ๐‘”โˆ’2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ๐œ”๐‘, and of the anomalous precession frequency corrected for beam dynamics effects, ๐œ”๐‘Ž. From the ratio ๐œ”๐‘Ž/๐œ”๐‘, together with precisely determined external parameters, we determine ๐‘Ž๐œ‡=116โ€‰592โ€‰057โข(25)ร—10โˆ’11 (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain ๐‘Ž๐œ‡โก(FNAL)=116โ€‰592โ€‰055โข(24)ร—10โˆ’11 (0.20 ppm). The new experimental world average is ๐‘Ž๐œ‡โก(exp)=116โ€‰592โ€‰059โข(22)ร—10โˆ’11 (0.19 ppm), which represents a factor of 2 improvement in precision. 
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    Free, publicly-accessible full text available October 17, 2024
  2. Free, publicly-accessible full text available November 1, 2024
  3. Abstract

    A description is presented of the algorithms used to reconstruct energy deposited in the CMS hadron calorimeter during Run 2 (2015โ€“2018) of the LHC. During Run 2, the characteristic bunch-crossing spacing for proton-proton collisions was 25 ns, which resulted in overlapping signals from adjacent crossings. The energy corresponding to a particular bunch crossing of interest is estimated using the known pulse shapes of energy depositions in the calorimeter, which are measured as functions of both energy and time. A variety of algorithms were developed to mitigate the effects of adjacent bunch crossings on local energy reconstruction in the hadron calorimeter in Run 2, and their performance is compared.

     
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    Free, publicly-accessible full text available November 1, 2024
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  7. Abstract

    A search for decays to invisible particles of Higgs bosons produced in association with a top-antitop quark pair or a vector boson, which both decay to a fully hadronic final state, has been performed using proton-proton collision data collected at$${\sqrt{s}=13\,\text {Te}\hspace{-.08em}\text {V}}$$s=13TeVby the CMS experiment at the LHC, corresponding to an integrated luminosity of 138$$\,\text {fb}^{-1}$$fb-1. The 95% confidence level upper limit set on the branching fraction of the 125$$\,\text {Ge}\hspace{-.08em}\text {V}$$GeVHiggs boson to invisible particles,$${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$B(Hโ†’inv), is 0.54 (0.39 expected), assuming standard model production cross sections. The results of this analysis are combined with previous$${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$B(Hโ†’inv)searches carried out at$${\sqrt{s}=7}$$s=7,ย 8, and 13$$\,\text {Te}\hspace{-.08em}\text {V}$$TeVin complementary production modes. The combined upper limit at 95% confidence level on$${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$B(Hโ†’inv)is 0.15 (0.08 expected).

     
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    Free, publicly-accessible full text available October 1, 2024
  8. Free, publicly-accessible full text available October 1, 2024
  9. Abstract

    The mass of the top quark is measured in 36.3$$\,\text {fb}^{-1}$$fb-1of LHC protonโ€“proton collision data collected with the CMS detector at$$\sqrt{s}=13\,\text {Te}\hspace{-.08em}\text {V} $$s=13TeV. The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state. For each event, the mass is reconstructed from a kinematic fit of the decay products to a top quark pair hypothesis. A profile likelihood method is applied using up to four observables per event to extract the top quark mass. The top quark mass is measured to be$$171.77\pm 0.37\,\text {Ge}\hspace{-.08em}\text {V} $$171.77ยฑ0.37GeV. This approach significantly improves the precision over previous measurements.

     
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    Free, publicly-accessible full text available October 1, 2024