RobustSigma - Robust Evaluation of the Nucleon Sigma Term with Lattice QCD
This project aims to deliver a precise and systematically controlled determination of the nucleon sigma term, a key quantity that encodes how the nucleon mass responds to changes in the light-quark masses and plays an essential role in nuclear physics, hadron structure, and dark-matter phenomenology. Building on high-quality lattice QCD ensembles at the physical point, the project will combine improved analysis strategies, targeted studies of continuum extrapolation, excited-state contamination, and cross-checks using multiple analysis approaches to ensure the robustness of the final result.
The continuum extrapolation will be performed using four physical-mass-point ensembles. A dedicated investigation of large source-sink separations and enhanced nucleon interpolators will be carried out on one physical-point ensemble, providing crucial input on systematic effects. The project will integrate all analyses into a coherent framework that quantifies uncertainties, ensures consistency across ensembles, and produces a final determination with fully controlled statistical and systematic errors.
Principal Investigator: Dr. Yan Li
Grant Agreement: RIF/EXCELLENCE/0925/0325
Additional Info
- Acronym: RobustSigma
- Website: Under construction
- Center: CaSToRC
- Funding Source: RIF/EXCELLENCE/0925
- CyI Funding: €107,348.00
- Funding Period: 2 years
- Starting Date: 1/9/2026
- End Date: 31/8/2028
- Coordinator: The Cyprus Institute
- Partners: University of Cyprus