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arXiv · 0901.4313

Covariant spectator theory for the electromagnetic three-nucleon form factors: Complete impulse approximation

Sérgio Alexandre Pinto·Alfred Stadler·Franz Gross
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Abstract

We present the first calculations of the electromagnetic form factors of $^3$He and $^3$H within the framework of the Covariant Spectator Theory (CST). This first exploratory study concentrates on the sensitivity of the form factors to the strength of the scalar meson-nucleon off-shell coupling, known from previous studies to have a strong influence on the three-body binding energy. Results presented here were obtained using the complete impulse approximation (CIA), which includes contributions of relativistic origin that appear as two-body corrections in a non-relativistic framework, such as "Z-graphs", but omits other two and three-body currents. We compare our results to non-relativistic calculations augmented by relativistic corrections of ${\cal O}(v/c)^2$.

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Sérgio Alexandre Pinto, Alfred Stadler, Franz Gross. 2009-01-27. Covariant spectator theory for the electromagnetic three-nucleon form factors: Complete impulse approximation. https://doi.org/10.1103/physrevc.79.054006

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