Search for η′ mesic nuclei by missing-mass spectroscopy of the ¹²C(p,d) reaction

¹ GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
² The University of Tokyo, Tokyo, Japan
³ RCNP, Osaka University, Osaka, Japan
⁴ Universidade de Santiago de Compostela, Santiago de Compostela, Spain
⁵ Universitä Giessen, Giessen, Germany
⁶ Kyoto University, Kyoto, Japan
⁷ KVI-CART, University of Groningen, Groningen, the Netherlands
⁸ Beihang University, Beijing, China
⁹ Nara Women’s University, Nara, Japan
¹⁰ KEK, Ibaraki, Japan
¹¹ Tottori University, Tottori, Japan
¹² RIKEN Nishina Center, Saitama, Japan
¹³ Tokyo Metropolitan University, Tokyo, Japan
¹⁴ Saint Mary’s University, Nova Scotia, Canada
¹⁵ Comenius University Bratislava, Bratislava, Slovakia
¹⁶ Stefan-Meyer-Institut für subatomare Physik, Vienna, Austria
¹⁷ Niigata University, Niigata, Japan

^* e-mail: y.tanaka@gsi.de

Published online: 29 November 2016

Abstract

We performed a missing-mass spectroscopy experiment of the ¹²C(p, d) reaction at 2.5 GeV proton energy in order to search for η′ mesic nuclei. An excitation-energy spectrum of ¹¹C was obtained around the η′ production threshold. As no significant peak structure was observed in the spectrum, upper limits of the formation cross section of η′ mesic nuclei have been determined. Preliminary results of the experiment as well as future prospects are given.