Speaker
Description
Moments of parton distribution functions encode fundamental information about the quark and gluon structure of hadrons. Their determination in lattice QCD using standard local operators is, however, limited by renormalization and mixing problems, particularly for higher moments. I will discuss a strategy based on local twist-two operators defined at positive gradient-flow time. At nonzero flow time, these operators have particularly simple renormalization properties and can be constructed so as to avoid power-divergent mixing. This makes it possible to take the continuum limit at fixed physical flow time before matching to physical PDF moments in the continuum through the short-flow-time expansion. I will describe the flowed-local-operator framework and present numerical applications to pion and nucleon PDF moments. These studies demonstrate the viability of the method and its potential to access higher moments that are difficult to determine with traditional local-operator techniques. I will also discuss the main statistical and systematic uncertainties, with particular emphasis on the continuum and short-flow-time extrapolations.