Associate strangeness production in near-threshold pp collisions
The cooler synchrotron COSY in Juelich allows for a precisely determined proton beam energy. It is therefore well suited for near-threshold measurements of meson production cross sections in pp collisions. The TOF collaboration determined the elementary cross section of associated strangeness production in the channel pp pLK+. This supplements the data basis in a energy region which is relevant for heavy-ion collisions. Together with other data from the COSY-11 collaboration one can now separate the final state interaction in the exit channel and determine the pure production cross section. Future measurements will focus on the reaction pp p S0 K+. The principle of the experiment, mainly due to the equipment of the Erlangen group, is based on observing directly behind the target 2 tracks of charged particles, namely p+ and K+, while after a longer distance 2 additional tracks emerge from the p+ and p decay products of the L. Physicists from Rossendorf participate in the TOF collaboration mainly togehter with colleagues from Technical University Dresden. Due to the thechnical services and infrastructure it was possible to build up the big barrel segment (length 3 meter, diameter 3 meter) in Rossendorf and to install it after test measurements at the COSY beam in Juelich.
for further information contact B. Kämpfer