Improving the Convergence of Chiral EFT for Few-Nucleon Systems

Download or read book Improving the Convergence of Chiral EFT for Few-Nucleon Systems written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decade chiral EFT has been applied by several groups to study the properties of fewâ nucleon systems based on the original idea of Weinberg [1], see [2] for a recent review. It is of utmost importance for all these applications to verify the convergence of the lowâ momentum expansion. As pointed out by Kaiser et al. [3], nucleonâ nucleon peripheral scattering provides an excellent ground to test the convergence of the chiral expansion. Indeed, the high angular momentum scattering states are dominated by the longâ range part of the nuclear force, where chiral dynamics is important. For example, no shortâ range contact interactions (with, in general, unknown coupling constants) contribute to Dâ and higher partial waves at nextâ nextâ toâ leading order (NNLO), which allows for parameterâ free calculations. In addition, the interaction between two nucleons becomes weak due to the centrifugal barrier, so that the Sâ matrix can be obtained using perturbative methods. It was found in [3].