Scalar-isovector K¯ production close to threshold
- 31 Downloads
The reaction pp → dK +¯ has been investigated at excess energies Q = 47.4 and 104.7MeV above the K +¯ threshold at COSY Jülich. Coincident dK+ pairs were detected with the ANKE spectrometer, and subsequently ∼ 2000 events with a missing ¯ invariant mass were identified, which fully populate the Dalitz plot. The joint analysis of invariant mass and angular distributions reveals s-wave dominance between the two kaons, in conjunction with a p-wave between the deuteron and the kaon pair, i.e. K¯ production via the a 0 +(980) channel. Integration of the differential distributions yields total cross-sections of σ(pp → dK +¯) = (38±2stat±14syst)nb and (190±4stat±39syst)nb for the low and high Q value, respectively.