High Precision for Hard Processes (HP2 2024)

Session

Subtraction, slicing and loop/tree duality

11 Sept 2024, 11:00

Room C1

Conveners

Subtraction, slicing and loop/tree duality

• Sandro Uccirati (Istituto Nazionale di Fisica Nucleare)

Subtraction, slicing and loop/tree duality

• Marco Rocco (Paul Scherrer Institut)

Subtraction, slicing and loop/tree duality

• There are no conveners in this block

45. Antenna Subtraction beyond NNLO

Matteo Marcoli (University of Durham)

11/09/2024, 11:00

Subtraction, slicing and loop/tree duality

In this talk I discuss the extension of the well-established antenna subtraction method beyond next-to-next-to-leading order in perturbative QCD. The definition of N3LO antenna functions for final-state radiation and their analytical integration are briefly reviewed. Subsequently, I analyse the structure of the subtraction terms needed to remove infrared singularities at N3LO in the context of...

69. A Numerical Implementation of the LASS Subtraction Scheme

Adam Kardos (University of Debrecen)

11/09/2024, 11:25

Subtraction, slicing and loop/tree duality

NNLO QCD corrections are indispensable for Today's and tomorrow's colliders. Several subtraction schemes are available in the literature. The LASS (Local Analytic Subtraction Scheme) as it is developed in Turin offers a possible way to obtain NNLO QCD predictions with this version of subtraction. Its simple analytical integrals make it tempting to generalize even to hadron collisions. Before...

56. Generalised Antenna Functions for Higher-Order Calculations

Elliot Fox (Durham University)

11/09/2024, 11:50

Subtraction, slicing and loop/tree duality

In the past few years, work has been done to construct antenna functions used in the antenna subtraction scheme directly from the limits we want them to have, rather than taking them directly from matrix elements. These "designer" antenna functions introduce fewer spurious singularities, and hence improve the simplicity of subtraction terms, especially at high multiplicity. Here, we report on...

41. Antenna subtraction for processes with identified particles at hadron colliders

Leonardo Bonino (University of Zurich)

12/09/2024, 11:00

Subtraction, slicing and loop/tree duality

Precise theoretical predictions for observables with identified hadrons at hadron colliders are essential to understand how partons fragment into hadrons. The hadronization process is parametrized by process-independent fragmentation functions that encode the parton-to-hadron transition. To incorporate hadron fragmentation in higher-order QCD calculations requires a subtraction method to...

44. Unresolved limits of polarised matrix elements

Markus Löchner (University of Zurich)

12/09/2024, 11:25

Subtraction, slicing and loop/tree duality

NNLO calculations in QCD require an analytic understanding of the infrared singular structure involving up to two unresolved partons. Up to now this was achieved only for unpolarized matrix elements. We report on the progress on the calculation of splitting amplitudes arising in longitudinally polarised QCD matrix elements at NNLO in the Larin ${\gamma }_5$ scheme. They are derived from DIS-like...

51. The NNLO soft function for N-jettiness in hadronic collisions

Rudi Rahn (University of Vienna)

12/09/2024, 11:50

Subtraction, slicing and loop/tree duality

In this talk I'll present our recent work calculating the N-jettiness soft function, based on an extension of the SoftSERVE framework to the general case of N+2 jets and beams for a priori general global observables. I will comment on our approach, present an explicit grid scanning the 2-jettiness soft function, and shed some light on the behaviour of the N-jettiness soft function at the edges...

60. New tools for $N$-jettiness computations

Ivan Pedron

12/09/2024, 12:15

Subtraction, slicing and loop/tree duality

The $N$-jettiness slicing has been a successful approach for the calculation of cross sections at next-to-next-to-leading order (NNLO) in perturbative QCD, and has a strong potential for computations at the following order. Recently we derived a compact representation of the renormalized $N$-jettiness soft function free of infrared and collinear divergences through NNLO. The convergence of the...

82. Local cancellation of IR singularities: an automated algorithm based on OpenLoops+LTD

Gloria Bertolotti (University of Sussex), Jonas Lindert (University of Sussex)

12/09/2024, 16:10

Subtraction, slicing and loop/tree duality

We elaborate on the construction of a new automated NLO generator developed within the OpenLoops framework. This new algorithm employs the Loop Tree Duality (LTD) method to achieve the local cancellation of IR singularities by directly combining virtual and real corrections at the integrand level. In this talk we focus on a novel technique that enables local IR cancellations in a general and...