Chiral effective field theory for few-nucleon systems: a new pertubative formulation and Pade summation.

• Applicant: Dr. Jambul Gegelia
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2011 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 190046547

Chiral effective field theory of strong interactions is applicable to the low energy sector, where the fundamental theory, the Quantum Chromodynamics, cannot be solved. Existing successful application of this approach to the few-nucleon sector uses the numerical methods and is based on the cutoff regularization. This method has a drawback that it violates the underlying symmetries. While the symmetry breaking contributions are formally of a higher order, the numerical calculations do not allow to accurately estimate their effect. Another nontrivial problem, following from the violation of underlying symmetries, is that the inclusion of the electromagnetic interaction within this formalism is very problematic. Recently we have suggested a new symmetry-preserving approach to chiral effective field theory. This approach has an important advantage that it preserves all symmetries of the theory. In this project, we propose to combine the advantages of the symmetry-preserving framework with the new formulation of the approach for nucleon-nucleon interaction with perturbative pions that has been suggested recently by Beane, Kaplan and Vuorinen.

• DFG Programme: Research Grants