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Two-body Pion Absorption on $^3He$ at Threshold

L. L. Kiang·T. -S. H. Lee·D. O. Riska
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Abstract

It is shown that a satisfactory explanation of the ratio of the rates of the reactions $^3He(π^-,nn)$ and $^3He(π^-,np)$ for stopped pions is obtained once the effect of the short range two-nucleon components of the axial charge operator for the nuclear system is taken into account. By employing realistic models for the nucleon-nucleon interaction in the construction of these components of the axial charge operator, the predicted ratios agree with the empirical value to within 10-20\%.

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L. L. Kiang, T. -S. H. Lee, D. O. Riska. 1994-04-28. Two-body Pion Absorption on $^3He$ at Threshold. https://doi.org/10.1103/physrevc.50.2703

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