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arXiv · 1705.10543

Missing-mass spectroscopy of the ${}^{12}{\rm C}(p,d)$ reaction near the $η^\prime$-meson production threshold

Abstract

Excitation-energy spectra of $^{11}$C nuclei near the $η^\prime$-meson production threshold have been measured by missing-mass spectroscopy using the $^{12}$C($p$,$d$) reaction. A carbon target has been irradiated with a 2.5 GeV proton beam supplied by the synchrotron SIS-18 at GSI to produce $η^\prime$ meson bound states in $^{11}$C nuclei. Deuterons emitted at $0^\circ$ in the reaction have been momentum-analyzed by the fragment separator (FRS) used as a high-resolution spectrometer. No distinct structure due to the formation of $η^\prime$-mesic states is observed although a high statistical sensitivity is achieved in the experimental spectra. Upper limits on the formation cross sections of $η^\prime$-mesic states are determined, and thereby a constraint imposed on the $η^\prime$-nucleus interaction is discussed.

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Y. K. Tanaka, K. Itahashi, H. Fujioka, Y. Ayyad, J. Benlliure, K. -T. Brinkmann, S. Friedrich, H. Geissel, J. Gellanki, C. Guo, E. Gutz, E. Haettner, M. N. Harakeh, R. S. Hayano, Y. Higashi, S. Hirenzaki, C. Hornung, Y. Igarashi, N. Ikeno, M. Iwasaki, D. Jido, N. Kalantar-Nayestanaki, R. Kanungo, R. Knoebel, N. Kurz, V. Metag, I. Mukha, T. Nagae, H. Nagahiro, M. Nanova, T. Nishi, H. J. Ong, S. Pietri, A. Prochazka, C. Rappold, M. P. Reiter, J. L. Rodríguez-Sánchez, C. Scheidenberger, H. Simon, B. Sitar, P. Strmen, B. Sun, K. Suzuki, I. Szarka, M. Takechi, I. Tanihata, S. Terashima, Y. N. Watanabe, H. Weick, E. Widmann, J. S. Winfield, X. Xu, H. Yamakami, J. Zhao. 2018-01-15. Missing-mass spectroscopy of the ${}^{12}{\rm C}(p,d)$ reaction near the $η^\prime$-meson production threshold. https://doi.org/10.1103/physrevc.97.015202

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