Chiral dynamics in few-nucleon systems

Conference · Wed Dec 01 04:00:00 EST 2004

OSTI ID:836339

Epelbaum, Evgeny

Chiral Effective Field Theory (EFT) has become a standard tool for analyzing the properties of hadronic systems at low energy in a systematic and controlled way based upon the approximate and spontaneously broken chiral symmetry of Quantum Chromodynamics (QCD). Based on Weinberg's idea to use chiral EFT to derive nuclear forces, this method has also been successfully applied to a few-nucleon problems. Energy-independent and hermitian nuclear potentials can be derived from the chiral Lagrangian e.g. using the method of unitary transformation. This scheme can also be applied to derive the corresponding nuclear current operator. They have used this framework to study the 2N system at next-to-next-to-next-to-leading order (N{sup 3}LO) in the chiral expansion. The theoretical uncertainty for scattering observables at N{sup 3}LO is expected to be of the order {approx} 0.5%, 7% and 25% at laboratory energy {approx} 50, 150 and 250 MeV. The findings agree well with these estimations. Three- and more-nucleon systems have been considered so far up to next-to-next-to-leading order. For the first time, the complete chiral three-nucleon force has been included in few-body calculations, which starts to contribute at this order. N{sup 3}LO analysis of > 2N systems is in progress. Recently they have worked out the leading and subleading isospin-violating 3N forces using the method of unitary transformation, which are largely driven by nucleon and pion mass differences. The work on isospin-breaking 2N forces is underway.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (US)
• Sponsoring Organization: USDOE Office of Energy Research (ER) (US)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 836339
• Report Number(s): JLAB-THY-05-299; DOE/ER/40150-3082
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
74 ATOMIC AND MOLECULAR PHYSICS
ATOMIC PHYSICS
CHIRAL SYMMETRY
FIELD THEORIES
LAGRANGIAN FUNCTION
MASS DIFFERENCE
NUCLEAR FORCES
NUCLEAR POTENTIAL
NUCLEONS
PIONS
QUANTUM CHROMODYNAMICS
SCATTERING