2024/05/31 by Lorenzo Barca, Gunnar Bali, Barca, Lorenzo +3 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2405.20875
openalex publication_date 2024/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nucleon weak matrix elements can be extracted from nucleon correlation functions with lattice QCD simulations. The signal-to-noise ratio prohibits the analysis at large source-sink separations and as a consequence, excited state contamination affects the extraction of the nucleon matrix elements. Chiral perturbation theory (ChPT) suggests that the dominant contamination in some of these channels is due to Nπ states where the pion carries the same momentum of the current. In this talk, we report updates on the variational analysis with qqq-operators (nucleon-like) and (qqq)(qq)-operators (nucleon-pion-like) where we report for the first time some preliminary results of ⟨ Nπ| J| N ⟩ , modulo some kinematic and volume factors, and we compare the results against ChPT. This pilot study is performed on a CLS ensemble with Nf=3, mπ≈ 420~MeV, a≈ 0.1~fm and T=2L≈ 4.8~fm.