Origin of Relativistic Effects in the Reaction D(e,e'p)n at GeV Energies

S. Jeschonnek; J. W. Van Orden

doi:10.1103/physrevc.62.044613

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Origin of Relativistic Effects in the Reaction D(e,e'p)n at GeV Energies

S. Jeschonnek·J. W. Van Orden

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Abstract

In a series of recent publications, a new approach to the non-relativistic reduction of the electromagnetic current operator in calculations of electro-nuclear reactions has been introduced. In one of these papers, the conjecture that at energies of a few GeV, the bulk of the relativistic effects comes from the current and not from the nuclear dynamics was made, based on the large relativistic effects in the transverse-longitudinal response. Here, we explicitly compare a fully relativistic, manifestly covariant calculation performed with the Gross equation, with a calculation that uses a non-relativistic wave function and a fully relativistic current operator. We find very good agreement up to missing momenta of 400 MeV/c, thus confirming the previous conjecture. We discuss slight deviations in cross sections for higher missing momenta and their possible origin, namely p-wave contributions and off-shell effects.

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S. Jeschonnek, J. W. Van Orden. 1999-11-17. Origin of Relativistic Effects in the Reaction D(e,e'p)n at GeV Energies. https://doi.org/10.1103/physrevc.62.044613

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