Helicity Methods for High Multiplicity Subleading Soft and Collinear Limits

Abstract

The factorization of multi-leg gauge theory amplitudes in the soft and collinear limits provides strong constraints on the structure of amplitudes, and enables efficient calculations of multi-jet observables at the LHC. There is significant interest in extending this understanding to include subleading powers in the soft and collinear limits. While this has been achieved for low point amplitudes, for higher point functions there is a proliferation of variables and more complicated phase space, making the analysis more challenging. By combining the subleading power expansion of spinor-helicity variables in collinear limits with consistency relations derived from the soft collinear effective theory, we show how to efficiently extract the subleading power leading logarithms of $N$-jet event shape observables directly from known spinor-helicity amplitudes. At subleading power, we observe the presence of power law singularities arising solely from the expansion of the amplitudes, which for hadron collider event shapes lead to the presence of derivatives of parton distributions. The techniques introduced here can be used to efficiently compute the power corrections for $N$-jettiness subtractions for processes involving jets at the LHC.

25 pages, 1 figure - v2: improvements to text and notation, journal version

References in corpus (10)

• Path integral approach to eikonal and next-to-eikonal exponentiation
• The method of regions and next-to-soft corrections in Drell-Yan production
• Subleading Power Rapidity Divergences and Power Corrections for $q_T$
• On next-to-eikonal corrections to threshold resummation for the Drell-Yan and DIS cross sections
• Leading-logarithmic threshold resummation of the Drell-Yan process at next-to-leading power
• One-loop phi-MHV amplitudes using the unitarity bootstrap
• Universality of next-to-leading power threshold effects for colourless final states in hadronic collisions
• Higher-twist corrections to gluon TMD factorization
• Collinear limits beyond the leading order from the scattering equations
• Subleading Jet Functions in Inclusive B Decays

Cited by in corpus (20)

• 50 Years of Quantum Chromodynamics
• Subleading Power Resummation of Rapidity Logarithms: The Energy-Energy Correlator in $\mathcal{N}=4$ SYM
• Diagrammatic resummation of leading-logarithmic threshold effects at next-to-leading power
• May the four be with you: Novel IR-subtraction methods to tackle NNLO calculations
• Subleading Power Factorization with Radiative Functions
• The Soft Quark Sudakov
• Next-to-leading power corrections to $V+1$ jet production in $N$-jettiness subtraction
• Impact of Isolation and Fiducial Cuts on $q_T$ and N-Jettiness Subtractions
• Factorization for Azimuthal Asymmetries in SIDIS at Next-to-Leading Power
• N-jettiness beam functions at N3LO
• Next-to-leading power threshold effects for inclusive and exclusive processes with final state jets
• Higher-order power corrections in a transverse-momentum cut for colour-singlet production at NLO
• Collinear expansion for color singlet cross sections
• ChiliPDF: Chebyshev Interpolation for Parton Distributions
• Threshold resummation of new partonic channels at next-to-leading power
• Factorization of Power Corrections in the Drell-Yan Process in EFT
• Power corrections in a transverse-momentum cut for vector-boson production at NNLO: the $qg$-initiated real-virtual contribution
• One-loop multicollinear limits from 2-point amplitudes on self-dual backgrounds
• The SAGEX Review on Scattering Amplitudes, Chapter 12: Amplitudes and collider physics
• Factorization at subleading power in deep inelastic scattering in the $x\to 1$ limit