Energy dependence of the Lambda/Sigma0 production cross section ratio in p-p interactions

P. Kowina; H. -H. Adam; A. Budzanowski; R. Czyzykiewicz; D. Grzonka; M. Janusz; L. Jarczyk; B. Kamys; A. Khoukaz; K. Kilian; P. Moskal; W. Oelert; C. Piskor-Ignatowicz; J. Przerwa; T. Rozek; R. Santo; G. Schepers; T. Sefzick; M. Siemaszko; J. Smyrski; A. Strzalkowski; A. Taschner; P. Winter; M. Wolke; P. Wustner; W. Zipper

doi:10.1063/1.1799807

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Energy dependence of the Lambda/Sigma0 production cross section ratio in p-p interactions

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Abstract

Measurements of the near threshold Lambda and Sigma0 production via the pp-->pK+Lambda/Sigma0 reaction at COSY--11 have shown that the Lambda/Sigma0 cross section ratio exceeds the value at high excess energies Q>=300 MeV by an order of magnitude. For a better understanding additional data have been taken between 13 MeV and 60 MeV excess energy. Within the first 20 MeV excess energy a strong decrease of the cross section ratio is observed, with a less steep decrease in the higher excess energy range. A description of the data with a parametrisation including p-Y final state interactions suggests a much smaller p-Sigma0 FSI compared to the p-Lambda system.

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P. Kowina, H. -H. Adam, A. Budzanowski, R. Czyzykiewicz, D. Grzonka, M. Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, K. Kilian, P. Moskal, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, T. Rozek, R. Santo, G. Schepers, T. Sefzick, M. Siemaszko, J. Smyrski, A. Strzalkowski, A. Taschner, P. Winter, M. Wolke, P. Wustner, W. Zipper. 2004-01-19. Energy dependence of the Lambda/Sigma0 production cross section ratio in p-p interactions. https://doi.org/10.1063/1.1799807

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