Inspire | HepData | Analysis reference | arXiv:1905.04242
A measurement of fiducial and differential cross-sections for $W^+W^-$ production in proton--proton collisions at $\sqrt{s}=$13 TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of $36.1$ fb$^{-1}$ is presented. Events with one electron and one muon are selected, corresponding to the decay of the diboson system as $WW\rightarrow e^{\pm}\nu\mu^{\mp}\nu$. To suppress top-quark background, events containing jets with a transverse momentum exceeding 35 GeV are not included in the measurement phase space. The fiducial cross-section, six differential distributions and the cross-section as a function of the jet-veto transverse momentum threshold are measured and compared with several theoretical predictions. Constraints on anomalous electroweak gauge boson self-interactions are also presented in the framework of a dimension-six effective field theory.
Inspire | HepData | Analysis reference | Phys.Rev.Lett. 121 (2018) no.15, 152002 | arXiv:1806.04667
This Letter presents a normalized differential cross-section measurement in a fiducial phase-space region where interference effects between top-quark pair production and associated production of a single top quark with a $W$ boson and a $b$-quark are significant. Events with exactly two leptons ($ee$, $\mu\mu$, or $e\mu$) and two $b$-tagged jets that satisfy a multiparticle invariant mass requirement are selected from 36.1 fb$^{-1}$ of proton-proton collision data taken at $\sqrt{s}=13$ TeV with the ATLAS detector at the LHC in 2015 and 2016. The results are compared with predictions from simulations using various strategies for the interference. The standard prescriptions for interference modeling are significantly different from each other but are within $2\sigma$ of the data. State-of-the-art predictions that naturally incorporate interference effects provide the best description of the data in the measured region of phase space most sensitive to these effects. These results provide an important constraint on interference models and will guide future model development and tuning.
Inspire | HepData | Analysis reference | arXiv:2009.00119 | CMS-SMP-18-004 | Phys. Rev. D 102 (2020) 092001
A measurement of the W W boson pair production cross section in proton-proton collisions at sqrt(s) = 13 TeV is presented. The data used in this study were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb-1. The W+W- candidate events are selected by first requiring two oppositely-charged leptons (electrons or muons). Two methods for reducing background contributions are employed. In the first one, a sequence of requirements on kinematic quantities is applied allowing a measurement of the total cross section: 117.6 +/- 6.8 pb which agrees well with the theoretical cross section. Fiducial cross sections are also reported for events with zero jets or one jet, and the change in the zero-jet fiducial cross section with the jet pT threshold is measured. Normalized differential cross sections are reported within the fiducial region; these are compared to theoretical predictions based on quantum chromodynamics at next-to-next-to-leading-order accuracy. A second method for suppressing background contributions employs two random forest classifiers. The analysis based on this method includes a measurement of the total cross section and also a measurement of the normalized jet multiplicity distribution in W+W- events. Finally, a dilepton invariant mass distribution is used to probe for physics beyond the standard model in the context of an effective field theory and limits on the presence of dimension-6 operators are derived.
Inspire | HepData | Analysis reference | arXiv:2005.01173 | CMS-SMP-19-012 | Phys. Lett. B 809 (2020) 135710
Measurements of production cross sections of WZ and same-sign W+W+ boson pairs in association with two jets in proton-proton collisions at sqrt{s}=13TeV at the LHC are reported. The data sample corresponds to an integrated luminosity of 137fb-1, collected with the CMS detector during 2016--2018. The measurements are performed in the leptonic decay modes. Differential fiducial cross sections as functions of the invariant masses of the jet and charged lepton pairs, as well as of the leading-lepton transverse momentum, are measured for WW production and are consistent with the standard model predictions. The dependence of differential cross sections on the invariant mass of the jet pair is also measured for WZ production. An observation of electroweak production of WZ boson pairs is reported with an observed (expected) significance of 6.8 (5.3) standard deviations. Constraints are obtained on the structure of quartic vector boson interactions in the framework of effective field theory.
Example: Eur.Phys.J. C76 (2016) no.7, 392 | Example: DOI:10.1140/epjc/s10052-016-4184-8 | Example: arXiv:1605.03814
A brief description of what is measured and what it is useful for. Use LaTeX for maths, e.g. $p_\perp > 50\;\text{GeV}$.
Jets with $p_\perp>20$ GeV are constructed with an anti-$k_\perp$ jet finder with $R=0.4$ and projected onto many different observables.
Monte Carlo validation observables for $W^+[e^+ \, \nu]W^-[\mu^- \, \nu]$ production
In addition to the typical jet observables this analysis contains observables related to properties of the WW-pair momentum, correlations between the WW, properties of the W bosons, properties of the leptons, correlations between the opposite charge leptons and correlations with jets.
Monte Carlo validation observables for $W^+[e^+ \, \nu]W^-[\mu^- \, \nu]$ + jets production