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arXiv · 2107.06748

Progress and Opportunities in Backward angle (u-channel) Physics

C. Ayerbe Gayoso·Ł. Bibrzycki·S. Diehl·S. Heppelmann·D. W. Higinbotham·G. M. Huber·S. J. D. Kay·S. R. Klein·J. M. Laget·W. B. Li·V. Mathieu·K. Park·R. J. Perry·B. Pire·K. Semenov-Tian-Shansky·A. Stanek·J. R. Stevens·L. Szymanowski·C. Weiss·B. -G. Yu
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Abstract

Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the u-channel, as discussed in the first backward angle (u-channel) Physics Workshop. In particular, we discuss backward angle measurements and their theoretical description via both hadronic models and the collinear factorization approach, and discuss planned future measurements of u-channel physics. Finally, we propose outstanding questions and challenges for u-channel physics.

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C. Ayerbe Gayoso, Ł. Bibrzycki, S. Diehl, S. Heppelmann, D. W. Higinbotham, G. M. Huber, S. J. D. Kay, S. R. Klein, J. M. Laget, W. B. Li, V. Mathieu, K. Park, R. J. Perry, B. Pire, K. Semenov-Tian-Shansky, A. Stanek, J. R. Stevens, L. Szymanowski, C. Weiss, B. -G. Yu. 2021-07-14. Progress and Opportunities in Backward angle (u-channel) Physics. https://doi.org/10.1140/epja/s10050-021-00625-2

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