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Radiative Muon Capture and Induced Pseudoscalar Coupling Constant in Nuclear Matter

Myung Ki Cheoun·K. S. Kim·B. S. Han·Il-Tong Cheon
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Abstract

The recent TRIUMF experiment for $μ^- p \to n ν_μ γ$ gave a surprising result that the induced pseudoscalar coupling constant $g_P$ was larger than the value obtained from $μ^- p \to n ν_μ$ experiment as much as 44 %. Reexamining contribution of the axial vector current in electromagnetic interaction, we found an additional term to the matrix element which was used to extract the $g_P$ value from the measured photon energy spectrum. This additional term, which plays a key role to restore the reliability of $g_P (- 0.88 m_μ^2) = 6.77 g_A (0)$, is shown to affect the $g_P$ quenching problems in nucleus.

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Myung Ki Cheoun, K. S. Kim, B. S. Han, Il-Tong Cheon. 1998-11-09. Radiative Muon Capture and Induced Pseudoscalar Coupling Constant in Nuclear Matter. https://arxiv.org/abs/nucl-th/9811025

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