Generating functionals for collinear fragmentation & resummation of groomed angularities and fractional moments of EEC

Pier Monni (CERN, Geneva)

Aug 31. 2023, 11:30 — 12:30

Jet calculus offers a unique mathematical technique to bridge the area of QCD resummation with Monte Carlo parton showers. With the ultimate goal of constructing next-to-next-to-leading logarithmic (NNLL) parton showers we study, using the language of generating functionals, the collinear fragmentation of final-state partons. In particular, we focus on the definition and calculation of the Sudakov form factor, which physically describes the no-emission probability in an ordered branching process. We review recent results for quark jets and compute the Sudakov form factor for the collinear fragmentation of gluon jets at NNLL. This provides the missing ingredients to extend the methods of jet calculus in the collinear limit to NNLL and gives an important element of the next generation of NNLL parton shower algorithms. As an application we derive new NNLL results for both the fractional moments of energyenergy correlation FCx and the angularities λx measured on mMDT/Soft-Drop (β = 0) groomed jets.

Further Information
ESI Schrödinger Lecture Hall
Associated Event:
Quantum Field Theory at the Frontiers of the Strong Interaction (Thematic Programme)
André H. Hoang (U of Vienna)
Simon Plätzer (U of Graz)
Massimiliano Procura (U of Vienna)
Malin Sjödahl (Lund U)
Iain Stewart (MIT, Cambridge)