Study of the hadronic production of kaon pairs below the threshold for the phi meson

Moskal, P.; Silarski, M.; Budzanowski, A.; Czerwinski, E.; Czyzykiewicz, R.; Gil, D.; Grzonka, D.; Janusz, M.; Jarczyk, L.; Kamys, B.; Khoukaz, A.; Klaja, P.; Oelert, W.; Piskor-Ignatowicz, C.; Przerwa, J.; Rejdych, B.; Ritman, J.; Sefzick, T.; Siemaszko, M.; Smyrski, J.; Taschner, A.; Winter, P.; Wolke, M.; Wustner, P.; Zielinski, M. J.; Zipper, W.; Zdebik, J.

Study of the hadronic production of kaon pairs below the threshold for the phi meson

Authors

Description

The near threshold production of K+K- pairs in proton-proton collisions has been investigated at the cooler synchrotron COSY below and above the threshold for the $ϕ$ meson using the COSY-11 and ANKE facilities, respectively. The excitation function determined for the pp-->ppK+K- reaction revealed a statistically significant enhancement close to the threshold which may plausibly be assigned to the influence of the K-p interaction. In addition, observed consistently by both groups, a strong enhancement at low values of the ratio of the K-p to K+p invariant mass distributions shows that the proton interacts much stronger with K- than with K+. In this report we focus on the measurements performed by the COSY-11 collaboration. We explain the experimental method used and present main results of completed analyses as well as a new qualitative elaboration of the ppK+K- events population on the Goldhaber plot. We conclude with the observation that event densities increase at the region where the influence from the K+K- interaction is expected.
5 pages, 5 figures, Talk given at International Workshop on e+ e- Collisions from Phi to Psi (PHIPSI08), Frascati, Italy, 7-10 Apr 2008