Ekta Chaubey

We study power corrections in the Drell-Yan (DY) process using state-of-the-art predictions for both neutral and charged current production. For both types of DY processes, we account for power corrections arising from bottom and charm quark effects within a variable flavor number scheme. Our results show that these corrections become significant in the low-$Q$ region. We also ensure proper treatment of overlapping contributions by carefully applying matching procedures to eliminate any double counting.

We study power corrections in the Drell–Yan (DY) process using state-of-the-art predictions for both neutral and charged current production. For both types of DY processes, we account for power corrections arising from bottom and charm quark effects within a variable flavor number scheme. Our results show that these corrections become significant in the low- Q region. We also ensure proper treatment of overlapping contributions by carefully applying matching procedures to eliminate any double counting.

In the well-studied genus zero case, bases of d log integrands with integer leading singularities define Feynman integrals that automatically satisfy differential equations in canonical form. Such integrand bases can be constructed without input from the differential equations and without explicit involvement of dimensional regularization parameter ε . We propose a generalization of this construction to genus one geometry arising from the appearance of elliptic curves. We argue that a particular choice of algebraic 1-forms of the second kind that avoids derivatives is crucial. We observe that the corresponding Feynman integrals satisfy a special form of differential equations that has not been previously reported, and that their solutions order by order in ε yield pure functions. We conjecture that our integrand-level construction universally leads to such differential equations.

In this talk, we discuss the progress made for a set of two-loop non-planar Feynman integrals containing massive internal propagators. These integrals are needed to compute NNLO QCD corrections to dijet and diphoton production. The corresponding Feynman integral topology contains a top-quark loop and is known to contain an elliptic curve.

We study a set of two-loop non-planar master integrals needed for the NNLO QCD corrections to diphoton and dijet production at hadron colliders. The top-sector topology contains an internal massive fermion loop and is known to contain elliptic curves. Leveraging the method of differential equations, we provide a comprehensive discussion for deriving an ϵ-factorized differential equation related to the most intricate sector within the Feynman integral family. Despite the dependence on multiple scales and the presence of two elliptic sectors, we demonstrate how to leverage the properties of their maximal cuts and the factorization of the Picard-Fuchs operator to deal with the complexity of the analytic computation. In particular, we construct a transformation matrix that brings the differential equations into a format enabling the convenient expression of analytic results in terms of Chen’s iterated integrals.

We present the analytic and compact two-loop helicity amplitudes for QCD and QED corrections to the light-by-light scattering process with massive internal fermions. We express the master integrals either in terms of multiple polylogarithms or in terms of iterated integrals with dlog one-forms. We also elaborate on optimizing the analytic results for each phase-space region. This makes the numerical evaluation of the scattering amplitudes fast, stable and suitable for phenomenological applications.