Beyond Collinear Factorization: Precision Measurement Era with Predictions from the Parton Branching TMDs.

Precision measurements have a prominent position at the Large Hadron Collider (LHC) as well as in the new accelerators' physics program and they relay on accurate theoretical predictions. In this proposal, a new way of obtaining predictions, the Parton Branching (PB) method, is discussed. The method, based on transverse momentum dependent (TMD) factorization theorem, aims in applicability to exclusive collider observables in a wide kinematic range. The basic element of cross sections calculations are parton distribution functions (PDFs). In contrast to the widely used collinear approach, the PB does not neglect the 3-dimensional structure of proton: the TMD PDFs (TMDs) are determined thanks to exact kinematic calculation. In this project outline an extensive theory program is proposed to establish connection between the PB and other approaches and to push the PB accuracy from next-to-leading logarithmic approximation to next-to-next-to-leading. The possibility of including small x together with small qt resummation within one approach by using TMD splitting functions will be investigated. The outcome of the project will be a big step forward in a common understanding of the TMD factorization and resummation. The theory developments will result in the new TMDs fit procedure within xFitter package, improved by incorporating the Drell-Yan data. The new TMDs will be used to obtain precise predictions for the crucial DY precision measurements at Run III and High Luminosity LHC.

Keywords:TMDS

Disciplines:Experimental particle physics, High energy physics, Phenomenological particle physics, Theoretical particle physics

Project type:Collaboration project