J. L. Friar

Chiral symmetry and three nucleon forces

After a brief review of the role three-nucleon forces play in the few-nucleon systems, the chiral-perturbation-theory approach to these forces is discussed. Construction of the (nominal) leading- and subleading-order Born terms and pion-rescattering graphs contributing to two-pion-exchange three-nucleon forces is reviewed, and comparisons are made of the types of such forces that are used today. It is demonstrated that the short-range {ital c} term of the Tucson-Melbourne force is unnatural in terms of power counting and should be dropped. The class of two-pion-exchange three-nucleon forces then becomes rather uniform. {copyright} {ital 1999} {ital The American Physical Society}

Chiral two-pion exchange and proton-proton partial-wave analysis

Published in: Phys. Rev. Lett. 82 (1999) 4992-4995 Citing articles (CrossRef) citations recorded in [Science Citation Index] Abstract: The chiral two-pion exchange component of the long-range pp interaction is studied in an energy-dependent partial-wave analysis. We demonstrate its presence and importance, and determine the chiral parameters c_i (i=1,3,4). The values agree well with those obtained from pion-nucleon amplitudes.

Nuclear Finite Size Effects in Light Muonic Atoms

Abstract The finite nuclear size corrections to the s-state energy levels of light muonic (or hydrogenic) atoms are calculated analytically through order (Zα)6. In addition to the usual expression of order (Zα)4, the (Zα)5, (Zα)6 and (Zα)6 log(Zα) contributions have been determined. These corrections have been separated into terms of nonrelativistic and relativistic orders. The results have been checked by solving perturbatively the exact eigenvalue equations of the Schroedinger and Dirac problems of a particle orbiting in the Coulomb field of a uniform charge distribution of fixed radius. Application is made to the case of the μ-4He atom. Finite-size contributions to the hydrogen Lamb shift and the relativistic recoil effect are briefly discussed.

pp-->pp pi 0 reaction near threshold: A chiral power counting approach.

We use power-counting arguments as an organizing principle to apply chiral perturbation theory, including an explicit

Nuclear sizes and the isotope shift

\Delta

Phenomenological aspects of isospin violation in the nuclear force

, to the

Triton calculations with the new Nijmegen potentials

p p \rightarrow p p \pi^0

Zemach moments for hydrogen and deuterium

reaction near threshold. There are two lowest-order leading mechanisms expected to contribute to the amplitude with similar magnitudes: an impulse term, and a

Nuclear electric dipole moment of 3He

\Delta

Charge symmetry breaking and the two pion exchange two nucleon interaction

-excitation mechanism. We examine formally sub-leading but potentially large mechanisms, including pion-rescattering and short-ranged contributions. We show that the pion-rescattering contribution is enhanced by off-shell effects and has a sign opposite to that of a recent estimate based on a PCAC pion interpolating field. Our result is that the impulse term interferes destructively with the pion rescattering and