Study of the 3He-eta system in d-p collisions at COSY-11

J. Smyrski; H. -H. Adam; A. Budzanowski; E. Czerwinski; R. Czyzykiewicz; D. Gil; D. Grzonka; A. Heczko; M. Janusz; L. Jarczyk; B. Kamys; A. Khoukaz; K. Kilian; P. Klaja; J. Majewski; P. Moskal; W. Oelert; C. Piskor-Ignatowicz; J. Przerwa; J. Ritman; T. Rozek; R. Santo; T. Sefzick; M. Siemaszko; A. Taeschner; P. Winter; M. Wolke; P. Wuestner; Z. Zhang; W. Zipper

arXiv · nucl-ex/0603023

Study of the 3He-eta system in d-p collisions at COSY-11

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Abstract

We present preliminary results from dp --> 3He X (X=pi0,eta) measurements near the eta production threshold. The data were taken during a slow ramping of the COSY internal deuteron beam scattered on a proton target. The 3He ejectiles were registered with the COSY-11 detection setup. The ongoing data analysis should deliver high precision data for the dp --> 3He eta total and differential cross sections for the excess energies in the range from threshold up to 9 MeV. The preliminary excitation function for the reaction dp --> 3He pi0 does not show any structure which could originate from the decay of 3He-eta bound state. We present also a threshold excitation curve for the dp --> 3He X channel. Contrary to corresponding results from SATURNE we see no cusp in the vicinity of the eta threshold.

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J. Smyrski, H. -H. Adam, A. Budzanowski, E. Czerwinski, R. Czyzykiewicz, D. Gil, D. Grzonka, A. Heczko, M. Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, K. Kilian, P. Klaja, J. Majewski, P. Moskal, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, J. Ritman, T. Rozek, R. Santo, T. Sefzick, M. Siemaszko, A. Taeschner, P. Winter, M. Wolke, P. Wuestner, Z. Zhang, W. Zipper. 2006-03-23. Study of the 3He-eta system in d-p collisions at COSY-11. https://arxiv.org/abs/nucl-ex/0603023

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