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arXiv · 2606.23067

Exploring Pion-Induced High-Momentum Components in Nuclei via $(p,p'\pi)$ Reactions

Junki Tanaka·Junichi Kato·Hiroshi Toki
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Abstract

Pion exchange plays a fundamental role in nuclear structure and is responsible for tensor correlations and high-momentum components in nuclei. The $(p,p'\pi)$ reaction provides a unique opportunity to investigate pion dynamics under large-momentum-transfer conditions. Its three-body kinematics allows large momentum transfer to be achieved while keeping the excitation energy of the residual nucleus low. We investigate the kinematical properties of the $^{12}\mathrm{C}(p,p'\pi^+)^{12}\mathrm{B}$ reaction using Lorentz-invariant three-body phase-space calculations. The calculations were performed for a 392-MeV proton beam assuming a constant transition amplitude. The resulting momentum-transfer map and phase-space distribution identify experimentally accessible regions of large momentum transfer and provide guidance for optimizing a double-arm spectrometer experiment at RCNP. The present study establishes a model-independent kinematical foundation for future investigations of pion-induced correlations, high-momentum components, and pion dynamics in nuclei.

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Junki Tanaka, Junichi Kato, Hiroshi Toki. 2026-06-22. Exploring Pion-Induced High-Momentum Components in Nuclei via $(p,p'\pi)$ Reactions. https://arxiv.org/abs/2606.23067

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