Precision measurement and interpretation of inclusive

Area of Science:

• High Energy Physics
• Particle Physics
• Quantum Chromodynamics (QCD)

Background:

• Precise measurements of electroweak boson production are crucial for understanding the Standard Model.
• Previous parton distribution function (PDF) analyses relied on limited collider data, necessitating improved constraints.

Purpose of the Study:

• To present high-precision measurements of inclusive W and Z/γ* Drell-Yan production cross sections.
• To derive an improved set of parton distribution functions (ATLAS-epWZ16) from LHC data and previous e±p scattering data.
• To determine the strange-to-light sea-quark density ratio and measure the CKM matrix element |Vcs|.

Main Methods:

• Analysis of proton-proton collision data at √s=7 TeV collected by the ATLAS detector.
• Measurement of W→ℓν and Z/γ*→ℓℓ (ℓ=e,μ) production cross sections as a function of lepton pseudorapidity and dilepton rapidity/mass.
• Global QCD analysis incorporating ATLAS Drell-Yan data with H1 and ZEUS inclusive e±p scattering cross-section data.

Main Results:

• Precise integrated and differential cross sections for W and Z/γ* Drell-Yan production were obtained.
• A new set of parton distribution functions, ATLAS-epWZ16, was derived, offering improved precision.
• The strange-to-light sea-quark density ratio was determined to be close to unity within the data's sensitivity range.
• A new measurement of the CKM matrix element |Vcs| was provided.

Conclusions:

• The high-precision ATLAS measurements significantly constrain parton distribution functions.
• The results provide a more accurate determination of the strange-to-light sea-quark ratio from collider data.
• The study contributes to a deeper understanding of proton structure and fundamental parameters of the Standard Model.