Measurement of the cross section in pp collisions at and validation of lepton analysis techniques

Area of Science:

• High Energy Physics
• Particle Physics
• Collider Physics

Background:

• The Standard Model (SM) of particle physics predicts specific properties of W boson production.
• Precise measurements of W boson cross sections are crucial for testing the SM and searching for new physics.
• The Large Hadron Collider (LHC) provides a unique environment for such high-precision measurements.

Purpose of the Study:

• To present a precise measurement of the W boson cross section in proton-proton collisions at a center-of-mass energy of 13 TeV.
• To validate novel analysis techniques applicable to future W boson lepton production studies.
• To determine the reconstruction efficiency and energy scale for W boson decays to hadronic final states.

Main Methods:

• Utilizing data collected by the Compact Muon Solenoid (CMS) experiment at the LHC.
• Analyzing an integrated luminosity of 41.5 fb^-1 of proton-proton collision data.
• Employing advanced techniques for W boson reconstruction and background estimation.

Main Results:

• The product of the inclusive cross section and branching fraction for W bosons was measured to be 100.4 ± 1.0 (stat.) ± 2.1 (syst.) nb.
• This result is in excellent agreement with the Standard Model expectation, calculated at next-to-next-to-leading order in perturbative quantum chromodynamics.
• Reconstruction efficiency and energy scale for W boson decays to hadrons were determined with relative uncertainties of 2.2% and 0.9%, respectively.

Conclusions:

• The measurement confirms the accuracy of Standard Model predictions for W boson production at 13 TeV.
• The validated analysis techniques will enhance future precision measurements of W boson lepton production.
• The determined efficiencies and energy scales are vital for precise W boson studies at the LHC.