Near-Threshold Production ofϕMesons inppCollisions

Authors :: P. Kulessa
V. I. Dimitrov
I. Keshelashvili
P. Wüstner
H. Ströher
H. Ohm
V. Hejny
V. Koptev
H. J. Stein
V. Kleber
M. Hartmann
Andreas Mussgiller
Markus Büscher
S. Barsov
K. Pysz
S. Mikirtytchiants
M. Nekipelov
R. Schleichert
M. S. Nioradze
S. Dymov
Yoshikazu Maeda
T. Mersmann
K. H. Watzlawik
W. Borgs
H.R. Koch
S. Merzliakov
Source :: Physical Review Letters. 96
Publication Year :: 2006
Publisher :: American Physical Society (APS), 2006.
Abstract: The pp ! ppreaction has been studied at the Cooler Synchrotron COSY-Julich, using the internal beam and ANKE facility. Total cross sections have been determined at three excess energiesnear the production threshold. The differential cross section closest to threshold at � � 18:5 MeV exhibits a clear S wave dominance as well as a noticeable effect due to the proton-proton final-state interaction. Taken together with data for pp! production, a significant enhancement of the �=! ratio of a factor 8 is found compared to predictions based on the Okubo-Zweig-Iizuka rule.