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Raynal's use of the word "aberrant" appears more appropriate for his ECIS formulation

K. Amos·L. Canton·G. Pisent·J. P. Svenne·D. van der Knijff
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Abstract

Recently, we published a paper (Nucl. Phys. A 728 (2003) 65; see nucl-th/0306068) presenting a new calculational method for nucleon-nucleus elastic scattering at low energies. That method is particularly appropriate for analyses in the region of narrow resonances. The method is based upon the sturmian representation of the S-matrix, and allows inclusion of nonlocality effects due to Pauli principle. It also provides a systematic identification of narrow-resonance spectra and subthreshold bound states. A phenomenological test calculation for low-energy (below 4 MeV) neutrons on 12-C (including the first two excitations of the target) was presented to illustrate the validity of the approach. The model calculation received a violent criticism (see nucl-th/0312038) by the developer of a method (ECIS) which to date cannot handle nonlocality effects and cannot be used easily to identify all narrow resonances. We demonstrate that Raynal's opposition to our development is not well founded by the arguments he presents. Indeed the work we published shows, on rewording the title of nucl-th/0312038, that it is ``aberrant'' phenomenologically to analyze resonant low-energy nucleon-nucleus processes with coupled-channel methods without taking into account the nonlocalities due to the Pauli principle; problems typically encountered in the ECIS formulation.

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K. Amos, L. Canton, G. Pisent, J. P. Svenne, D. van der Knijff. 2004-01-27. Raynal's use of the word "aberrant" appears more appropriate for his ECIS formulation. https://arxiv.org/abs/nucl-th/0401055

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