Annual report / Kernforschungsanlage Jülich Institut für Kernphysik. 1988

In July the official ceremony for laying the foundation-stone for the cooler synchrotron COSY- Jülich was celebrated. At this opportunity the universities of Nordrhein-Westfalen, organized in CANU et al., and the KFA signed an agreement to collaborate in the field of medium energy physics experiments at COSY. The main tasks of the institute in 1988 were to propose an experimental programm for COSY and the upgrading of the cyclotron as COSY-injector. These tasks were discussed in several workshops: (i) for detector design and development (July, KFA-IKP), (ii) for medium energy physics (September, Manderscheid/Eifel) and (iii) for proposed experiments at COSY (December, Bad Honnef). In collaboration with various divisions of the KF A infrastructure the insti tute participates in the realization of the COSY-project. The design and progress in the realization of COSY was examined by diffeent advisory committees (KEB, SCC). The most important results in our current research programm in 1988 are: (i) Observation of high energy bremsstrahlung in connection with investigations of giant resonances in hot nuclei. (ii) A discrete superdeformed band was identified in $^{146}$Gd by the OSIRIS-collaboration; also in $^{180}$Os Superdeformation was observed. (iii) The double-magic nucleus $^{96}$Zr shows a strong octupol-collectivity in a certain transition to the groundstate. (iv) In the antiproton-protron reaction $\overline{p}$p $\rightarrow$ $\overline{A}$A at LEAR/ CERN near threshold a strong p-wave dominance was observed and it was confirmed that the $\overline{A}$A production occurs in a triplet state only. (v) The theoretical interpretation for the dominant $\overline{A}$A p-wave is the existence for a resonance state in this region