Gravitational transition form factors of N → ∆ via QCD light-cone sum rules

Abstract

We present the first direct calculation on the gravitational form factors (GFFs) of the N → ∆ transition using an analytic method, the QCD light-cone sum rules. The matrix element of the quark part of the energy momentum tensor current sandwiched between the nucleon and ∆ states are parameterized in terms of five independent conserved and four independent non-conserved GFFs, for calculation of which we use the distribution amplitudes (DAs) of the on-shell nucleon expanded in terms of functions with different twists. We present the results for two sets of light-cone input parameters. The results indicate that the behavior of the form factors with respect to Q2 are described by multipole fit functions. Our results may be checked by other phenomenological models including the Lattice QCD as well as future related experiments.

Nucleon-Pion Spectroscopy from Sparsened Correlators

“…The Δ(1232) plays an important role in these processes, and achieving percent-level precision in nuclear-many-body predictions of neutrino-nucleus scattering will require theoretical predictions of 𝑁 → Δ transition form factors with few-percent precision [9]. Current phenomenological determinations and QCD model predictions of axial 𝑁 → Δ transition form factors only achieve 10-20% precision [10][11][12][13]. Lattice QCD studies of pion-and Δ-production amplitudes that could improve constraints on these and other form factors are therefore essential for achieving percent-level precision on neutrino-nucleus cross sections.…”