Factorization in the Soft Collinear Effective Theory Beyond Leading Power

• Iain Stewart (MIT)

In this talk I will describe the methods used in SCET to describe power suppressed amplitudes and factorized hard, jet, and soft functions.  I'll also discuss applications to threshold resummation.

Discussion

Threshold logarithms beyond leading power in perturbative QCD

• Lorenzo Magnea (University of Turin)

Discussion

Helicity Operators in SCET

• Wouter Waalewijn (University of Amsterdam)

I will present an easy-to-use helicity operator basis in soft-collinear effective theory (SCET), for which the hard Wilson coefficients from matching QCD onto SCET are directly given in terms of color-ordered helicity amplitudes. This allows one to seamlessly combine fixed-order helicity amplitudes at any order they are known with a resummation of higher-order logarithmic corrections. I will illustrate this by a few examples and discuss the role of renormalization schemes with helicities in 4- and d-dimensions, and discrete symmetries. The corresponding subleading operators will be introduced in a separate talk by Ian Moult.

Discussion

Next-to-leading power factorization with position-space SCET

• Martin Beneke (TUM, Munich)

I review position-space SCET as a framework to address next-to-leading power effects and discuss the following applications: semi-inclusive DIS on a heavy quark, the LBKD amplitude at tree level, and resummation of the three-body heavy quark currents.

Discussion

A Factorisation Approach to Soft Radiation in Drell-Yan Beyond Leading Power

• Leonardo Vernazza (University of Edinburgh)

Discussion

Subleading Soft Theorems in SCET

• Andrew Larkoski (Harvard University)

Using factorization properties of soft-collinear effective theory, I will discuss the construction of soft theorems at subleading power.  Soft gluon emission in SCET is described by operators and Lagrangians whose form is dictated by the reparametrization invariance of the effective theory.  In explicit examples, I will demonstrate how collinear emissions affect the soft theorems and their generalization to one-loop as predicted by SCET.

Discussion

Soft Expansion by Region and Higgs Production

• Franz Herzog (Nikhef, Amsterdam)

I will discuss the apllication of the method of expansion by region to obtain soft expansions of loop integrals required in Higgs Production beyond leading order.

Discussion

TBA

• Ian Moult (MIT)

Discussion

Resummation from the D-dimensional structure of unfactorized cross section

• Adriano Lo Presti (University of Zurich)

For inclusive enough processes, the structure of unfactorized parsonic cross sections, together with constraints from mass-factorization theorems, allows the resummation of logarithms beyond the leading power. I present the application of this method to the off-diagonal parsonic cross section of inclusive Higgs production and Drell-Yan, as well as to the off-diagonal splitting functions and the corresponding coefficient functions in inclusive deep-inelastic scattering and semi-inclusive electron-positron annihilation.

Discussion

(Next-to) soft effects in gravity

• Chris White (University of Glasgow)

In QCD, (next-to) soft physics is important for improving collider physics predictions. However, there are also a number of reasons for exploring similar effects in gravity. This talk will review the structure of soft and next-to-soft corrections in gravity, and focus on a number of recent applications, including the relationship between Yang-Mills and gravity amplitudes; the next-to-soft theorems of Cachazo and Strominger and their possible role in black hole physics; and transplanckian scattering.

Round Table