6533b85efe1ef96bd12bff80

RESEARCH PRODUCT

Renormalization and Scale Evolution of the Soft-Quark Soft Function

Xing WangSean FlemingMatthias NeubertMatthias NeubertBianka MecajZe Long Liu

subject

QuarkHigh Energy Physics - TheoryNuclear and High Energy PhysicsHigh Energy Physics::LatticeFOS: Physical sciencesPosition and momentum spaceRenormalizationsymbols.namesakeHigh Energy Physics - Phenomenology (hep-ph)FactorizationPerturbative QCDRenormalization Grouplcsh:Nuclear and particle physics. Atomic energy. RadioactivityResummationMathematical physicsPhysicsHigh Energy Physics::PhenomenologyPropagatorEffective Field TheoriesRenormalization groupHigh Energy Physics - PhenomenologyHigh Energy Physics - Theory (hep-th)Weierstrass factorization theoremsymbolslcsh:QC770-798High Energy Physics::ExperimentResummation

description

Soft functions defined in terms of matrix elements of soft fields dressed by Wilson lines are central components of factorization theorems for cross sections and decay rates in collider and heavy-quark physics. While in many cases the relevant soft functions are defined in terms of gluon operators, at subleading order in power counting soft functions containing quark fields appear. We present a detailed discussion of the properties of the soft-quark soft function consisting of a quark propagator dressed by two finite-length Wilson lines connecting at one point. This function enters in the factorization theorem for the Higgs-boson decay amplitude of the $h\to\gamma\gamma$ process mediated by light-quark loops. We perform the renormalization of this soft function at one-loop order, derive its two-loop anomalous dimension and discuss solutions to its renormalization-group evolution equation in momentum space, in Laplace space and in the "diagonal space", where the evolution is strictly multiplicative.

yearjournalcountryeditionlanguage
2020-07-16
10.1007/jhep07(2020)104http://arxiv.org/abs/2005.03013