a+0 (980)-resonance production in pp-->dK+K-0 reactions close to threshold

Phys Rev Lett. 2003 Oct 24;91(17):172304. doi: 10.1103/PhysRevLett.91.172304. Epub 2003 Oct 24.

Abstract

The reaction pp-->dK+K(-)0 has been investigated at an excess energy of Q=46 MeV above the K+K(-)0 threshold with ANKE at the cooler synchrotron COSY-Jülich. From the detected coincident dK(+) pairs, about 1000 events with a missing K(-)0 were identified, corresponding to a total cross section of sigma(pp-->dK+K(-)0)=[38+/-2(stat)+/-14(syst)] nb. Invariant-mass and angular distributions have been jointly analyzed and reveal s-wave dominance between the two kaons, accompanied by a p wave between the deuteron and the kaon system. This is interpreted in terms of a(+)0 (980)-resonance production.