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arXiv · 0709.4450

Understanding the Forward Muon Deficit in Coherent Pion Production

L. M. Sehgal
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Abstract

For any inelastic process $v_{\ell} + I \to \ell^- + F$ with $m_{\ell} = 0$, the cross section at $θ_{\ell} = 0$ is given by Adler's PCAC theorem. Inclusion of the lepton mass has a dynamical effect (``PCAC-screening'') caused by interference of spin-zero ($π^+$) and spin-one exchanges. This effect may be relevant to the forward suppression reported in recent experiments.

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L. M. Sehgal. 2007-09-27. Understanding the Forward Muon Deficit in Coherent Pion Production. https://doi.org/10.1063/1.2834469

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