# A Complete Basis of Helicity Operators for Subleading Factorization

## TL;DR

This paper develops a complete basis of helicity operators for subleading power factorization in QCD processes, enhancing precision and understanding of power corrections in high-energy physics calculations.

## Contribution

It constructs the first comprehensive set of subleading helicity operators for key scattering processes using SCET, including the first two subleading orders.

## Key findings

- Provides a complete basis of operators for subleading power factorization.
- Analyzes the structure of hard, jet, and soft functions at subleading order.
- Offers lowest order matching results for these operators.

## Abstract

Factorization theorems underly our ability to make predictions for many processes involving the strong interaction. Although typically formulated at leading power, the study of factorization at subleading power is of interest both for improving the precision of calculations, as well as for understanding the all orders structure of QCD. We use the SCET helicity operator formalism to construct a complete power suppressed basis of hard scattering operators for $e^+e^-\to$ dijets, $e^- p\to e^-$ jet, and constrained Drell-Yan, including the first two subleading orders in the amplitude level power expansion. We analyze the form of the hard, jet, and soft function contributions to the power suppressed cross section for $e^+e^-\to$ dijet event shapes, and give results for the lowest order matching to the contributing operators. These results will be useful for studies of power corrections both in fixed order and resummed perturbation theory.