6533b82cfe1ef96bd128ff0a
RESEARCH PRODUCT
From deep inelastic scattering to heavy-flavor semi-leptonic decays: Total rates into multi-hadron final states from lattice QCD
Maxwell T. HansenHarvey B. MeyerDaniel Robainasubject
PhysicsQuantum chromodynamicsParticle physicsFinite volume method010308 nuclear & particles physicsHigh Energy Physics::LatticeHigh Energy Physics - Lattice (hep-lat)High Energy Physics::PhenomenologyHadronLattice field theoryFOS: Physical sciencesLattice QCDQuantum numberDeep inelastic scattering01 natural sciencesHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - Lattice0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsLeptondescription
We present a new technique for extracting decay and transition rates into final states with any number of hadrons. The approach is only sensitive to total rates, in which all out-states with a given set of QCD quantum numbers are included. For processes involving photons or leptons, differential rates with respect to the non-hadronic kinematics may also be extracted. Our method involves constructing a finite-volume Euclidean four-point function, whose corresponding spectral function measures the decay and transition rates in the infinite-volume limit. This requires solving the inverse problem of extracting the spectral function from the correlator and also necessitates a smoothing procedure so that a well-defined infinite-volume limit exists. Both of these steps are accomplished by the Backus-Gilbert method and, as we show with a numerical example, reasonable precision can be expected in cases with multiple open decay channels. Potential applications include nucleon structure functions and the onset of the deep inelastic scattering regime, as well as semi-leptonic $D$ and $B$ decay rates.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2017-04-28 |