2004/07/30 by M. Pavon Valderrama, Manuel Pavón Valderrama, E. Ruiz Arriola +2
Earth and Planetary Sciences · Mathematics · Physics and Astronomy · #Advanced Mathematical Physics Problems #Electromagnetic Scattering and Analysis #FOS: Physical sciences #Nuclear Theory (nucl-th) #Seismic Imaging and Inversion Techniques #nucl-th
paper · pdf · doi:10.48550/arxiv.nucl-th/0407113
7 figures, 5 tables
arxiv created 2004/07/30 · openalex publication_date 2004/07/30 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The Variable S-matrix approach offers a unique way to extract low energy threshold parameters for a given NN potential. We extract those parameters for the np system from the NijmII and Reid93 potentials, to all partial waves with total angular momentum j ≤ m5 , using the generalized effective range expansion % (\bf fsj)l,l' kl kl' = -(\bf asj-1)l,l' + \frac12 (\bf rsj)l,l' k2 + (\bf v2sj)l,l' k4 + + (\bf v3sj)l,l' k6 + + (\bf v4sj)l,l' k8 + ... - \rm i kl+l'+1 % where \bf fsj = (\bf Ssj - \bf 1) / (2 \rm i k) is the scattering amplitude and \bf Ssj is the unitary S-matrix in coupled channel space with total spin s and total angular momentum j. Our calculation includes all the relevant contributions of the full amplitude to order \cal O (k8) in the CM momentum. We also discuss the validity of the generalized effective range expansion in the region of analyticity k ≤ mπ/2.