https://doi.org/10.1051/epjconf/20123709004
Isospin Decomposition of the Basic Double-Pionic Fusion in the Region of the ABC Effect
1 Physikalisches Institut, Univ. Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany
2 Kepler Center for Astro and Particle Physics, Univ. Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen
a e-mail: clement@pit.physik.uni-tuebingen.de
With a proton beam of Tp = 1.2 GeV incident on the deuterium pellet target of the WASA detector setup all three basic double-pionic fusion reactions have been measured simultaneously. By use of quasifree kinematics the energy range 2.3 GeV ≤ √s < 2.5 GeV could be covered, which just coincides with the energy region, where the ABC effect and its associated resonance structure has been observed. From the isospin decomposition we see that the resonance effect is solely in the isoscalar part of the reaction process, whereas the isovector part exhibits a monotonic smoothly rising energy dependence and no ABC effect.
© Owned by the authors, published by EDP Sciences, 2012
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.