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$Σ$ Like Term in Pion Electroproduction Near Threshold

Myung Ki Cheoun·Shin Nan Yang·Bong Soo Han·Il-Tong Cheon
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Abstract

Sum of the time component of $Σ$ term and the induced pseudo scalar term in axial current is shown to be the t-channel pion pole in Born terms for pion electroproduction near threshold. We also show that this $Σ$ term represents the charged pseudo scalar quark density matrix elements in nucleon and manifests itself in the $L_0^+$ amplitude on this reaction.

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Myung Ki Cheoun, Shin Nan Yang, Bong Soo Han, Il-Tong Cheon. 1997-02-19. $Σ$ Like Term in Pion Electroproduction Near Threshold. https://arxiv.org/abs/nucl-th/9702041

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