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Exploring the nuclear pion dispersion relation through the anomalous coupling of photon to photon and neutral pion

Alexander Volya·Kevin Haglin·Scott Pratt·Vladimir Dmitriev
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Abstract

We investigate the possibility of measuring the pion dispersion relation in nuclear matter through the anomalous coupling in the reaction γ- γ' π_0. It is shown that this reaction permits the study of pionic modes for space-like momenta. If the pion is softened in nuclear matter due to mixing with the delta-hole state, significant strength for this reaction is expected to move into the space-like region. Competing background processes are evaluated, and it is concluded that useful insight can be obtained experimentally, but only through a difficult exclusive measurement.

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Alexander Volya, Kevin Haglin, Scott Pratt, Vladimir Dmitriev. 1998-06-12. Exploring the nuclear pion dispersion relation through the anomalous coupling of photon to photon and neutral pion. https://doi.org/10.1088/0954-3899%2F25%2F10%2F305

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