Related papers: The LBK theorem to all orders
Predictions for processes involving soft photons, up to next-to-leading power (NLP) in the photon energy, can be obtained using the Low-Burnett-Kroll (LBK) theorem. The consistency of the theorem has been a recent topic of investigation…
The study of next-to-leading-power (NLP) corrections in soft emissions continues to attract interest both in QCD and in QED. Soft-photon spectra in particular provide a clean case-study for the experimental verification of the…
This paper derives a next-to-leading power (NLP) soft theorem for multi-photon emission to all orders in the electromagnetic coupling constant, generalising the leading-power theorem of Yennie, Frautschi, and Suura. Working in the QED…
We present two novel results about the universal structure of radiative QED amplitudes in the soft and in the collinear limit. On the one hand, we extend the well-known Low-Burnett-Kroll theorem to the one-loop level and give the explicit…
We discuss the linear power corrections to the electroweak production of top quarks at the LHC using renormalon calculus. We show how such non-perturbative corrections can be obtained using the Low-Burnett-Kroll theorem, which provides the…
We derive the QCD$\times$QED factorization theorem governing the leptonic decay $B^-\to\mu^-\bar\nu_\mu(\gamma)$ at all orders in $\alpha_s$ and $\alpha$. Electromagnetic corrections to this decay probe multiple scales, which we disentangle…
Threshold logarithms become dominant in partonic cross sections when the selected final state forces gluon radiation to be soft or collinear. Such radiation factorizes at the level of scattering amplitudes, and this leads to the resummation…
Working to all orders in dimensionally-regularized QCD, we study the radiation of a photon whose energy is much lower than that of external partons, but much larger than the masses of some quarks. We argue that the conventional soft photon…
We discuss all-order factorization for the virtual Compton process at next-to-leading power (NLP) in the $\Lambda_{\rm QCD}/Q$ and $\sqrt{-t}/Q$ expansion (twist-3), both in the double-deeply-virtual case and the single-deeply-virtual case.…
We study the first power correction to the heavy electron form factor in QED and show that it factorizes as a derivative operator. We discuss the result in QED with no light fermions, where the first power correction can be written…
Soft and collinear radiation is responsible for large corrections to many hadronic cross sections, near thresholds for the production of heavy final states. There is much interest in extending our understanding of this radiation to…
The complete set of ${\cal O}(\alpha)$ QED corrections with soft photon exponentiation to the process $ep \rightarrow eX$ in mixed variables ($y=y_h,Q^2=Q_l^2$) is calculated in the quark parton model, including the lepton-quark…
We generalise the factorization of abelian gauge theory amplitudes to next-to-leading power (NLP) in a soft scale expansion, following a recent generalisation for Yukawa theory. From an all-order power counting analysis of leading and…
It is well known that cross-sections in perturbative QCD receive large corrections from soft and collinear radiation, whose properties must be resummed to all orders in the coupling. Whether or not the universal properties of this radiation…
We calculate next-to-leading-order (NLO) corrections to exclusive processes in $k_T$ factorization theorem, taking $\pi\gamma^*\to\gamma$ as an example. Partons off-shell by $k_T^2$ are considered in both the quark diagrams from full QCD…
The emission of soft radiation provides a fundamental probe of the consistency of the underlying quantum field theory. Correspondingly, the measurement of the soft photon bremsstrahlung, such as the one proposed with the planned future…
We compute the virtual next-to-leading corrections to the impact factors or off-shell coefficient functions in the high-energy limit. When combined with the known real corrections, these results will provide the complete NLO corrections to…
We present a treatment of the next-to-leading-order radiative corrections to unpolarized Moller and Bhabha scattering without resorting to ultra-relativistic approximations. We extend existing soft-photon radiative corrections with new…
We define soft quark operators that enable construction of colour-ordered helicity amplitudes out of the non-radiative ones. We explore these operators for Higgs plus one jet production in a hadron collider and study the next-to-leading…
Control over quantum electrodynamics (QED) radiative corrections is critical for precise determination of neutrino oscillation probabilities from observed (anti)neutrino detection rates. It is particularly important to understand any…