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On isovector meson exchange currents in the Bethe-Salpeter approach

S. G. Bondarenko·V. V. Burov·M. Beyer·S. M. Dorkin
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Abstract

We investigate the nonrelativistic reduction of the Bethe-Salpeter amplitude for the deuteron electrodisintegration near threshold energies. To this end, two assumptions have been used in the calculations: 1) the static approximation and 2) the one iteration approximation. Within these assumptions it is possible to recover the nonrelativistic result including a systematic extension to relativistic corrections. We find that the so-called pair current term can be constructed from the $P$-wave contribution of the deuteron Bethe-Salpeter amplitude. The form factor that enters into the calculation of the pair current is constrained by the manifestly gauge independent matrix elements.

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S. G. Bondarenko, V. V. Burov, M. Beyer, S. M. Dorkin. 1998-09-12. On isovector meson exchange currents in the Bethe-Salpeter approach. https://doi.org/10.1103/physrevc.58.3143

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