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Lorentz contraction, geometry and range in antiproton-proton annihilation into two pions

B. El-Bennich·W. M. Kloet
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Abstract

We present a geometric interpretation of the so-called annihilation range in reactions of the type $\bar pp \to$ {\em two light mesons} based upon Lorentz effects in the highly relativistic final states ($γ=E_{\mathrm{cm}}/2mc^2\simeq 6.8-8.0$). Lorentz-boosted meson wave functions, within the framework of the constituent quark model, result in a richer angular dependence of the annihilation amplitudes and thus in higher partial wave contributions ($J>1$) than usually obtained. This approach sheds some light on what could be a "{\em short}" annihilation range and how it is influenced by the angular distribution of the final states.

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B. El-Bennich, W. M. Kloet. 2005-06-29. Lorentz contraction, geometry and range in antiproton-proton annihilation into two pions. https://doi.org/10.1063/1.2130132

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