Resumming transverse observables for NNLO+PS matching in GENEVA

TL;DR

This paper advances the GENEVA framework by integrating higher-order resummation techniques for transverse observables, enabling more precise NNLO+PS matching, demonstrated through Higgs production in heavy-quark annihilation.

Contribution

It introduces the embedding of $q_T$ resummation at N$^3$LL and the use of generalized $N$-jettiness for improved parton shower matching within GENEVA.

Findings

Achieved NNLO+PS matching for Higgs production using transverse measures.

Implemented $q_T$ resummation at N$^3$LL accuracy.

Resummed one-jettiness at NLL$'$ accuracy.

Abstract

We study the use of higher-order resummation for transverse observables to achieve NNLO+PS matching within the GENEVA framework. In particular, we embed $q_T$ resummation for colour-singlet production at N$^3$LL obtained via soft-collinear effective theory and implemented in the library SCETlib within GENEVA. We also study for the first time the use of the generalised $N$-jettiness variable in parton shower matching, and achieve the resummation of the one-jettiness defined with transverse measures up to NLL$'$ accuracy. As a case study, we use these resummed calculations to construct a GENEVA NNLO+PS generator for Higgs boson production in heavy-quark annihilation (with beauty or charm-quarks in the initial state). The use of transverse measures facilitates the matching to showers ordered in transverse momentum, and opens the door to possible future extensions of this approach to the production of colour singlets in association with final-state jets.