A physical interpretation of the discrete ambiguities in the optical potential for composite particles

Breakup mechanisms in the He6+Zn64 reaction at near-barrier energies

“…Since some ambiguities of the breakup cross section obtained from DWBA calculations have been observed from different potentials which reproduce the entrance channel in Refs. [31][32][33][34][35], we have calculated the NEB angular distributions with two different potentials at 14.85 MeV. One is the optical model potential from Table I (OM 1), which reproduces better the experimental data in terms of χ 2 , and the second optical model (OM 2) has been forced to reproduce the experimental data in the vicinity of the rainbow peak, yielding v = 5.71 MeV, r = 0.99 fm, a 0 = 1.99 fm, w = 0.25 MeV, r i = 1.86 fm, and a i = 0.99 fm (see left-hand side of Fig.…”

“…Since some ambiguities of the breakup cross-section obtained from DWBA calculations have been observed from different potentials which reproduce the entrance channel in Refs. [32][33][34][35][36], we have calculated the NEB angular distributions with two different potentials at 14.85 MeV.…”

Supersymmetric transformations in coupled-channel systems

“…As a realistic example we consider the 3 S 1 -3 D 1 partial waves of the nucleon-nucleon (NN) system which are coupled by a tensor potential that sustains a single physical bound state at E d = −2.22 MeV (the deuteron). Within the quark model the NN force is an effective interaction of a composite particle system and may give rise to Pauli-forbidden states which are simulated by deep unphysical bound states in local potential models [11]. Neudatchin et al [18] were the first to use the concept of forbidden states for the NN potential.…”

“…2 are phase equivalent. The introduction of bound states via the twice iterated SUSY transformation (9)(10)(11) is also possible for systems where channels with different quantum numbers of orbital angular momentum are coupled. Of particular interest is the coupling of an s-channel (ℓ 1 = 0) and a d-channel (ℓ 2 = 2) when the associated potential has only in the d-channel an 1/r 2 -singularity at the origin.…”

“…An important application is the relationship of equivalent effective interactions between composite particle systems. In such systems, because of the necessary suppression of the internal degrees of freedom, the resulting interactions are ambiguous [11,12]. There is always a set of effective interactions leading to the same scattering phase shifts which sustain, however, a different number of additional unphysical bound states as a consequence of simulating differently the Pauli principle.…”