Production ofK+K−pairs in proton-proton collisions at 2.83 GeV

Abstract

Differential and total cross sections for the pp → ppK + K − reaction have been measured at a proton beam energy of 2.83 GeV using the COSY-ANKE magnetic spectrometer. Detailed model descriptions fitted to a variety of one-dimensional distributions permit the separation of the pp → ppφ cross section from that of non-φ production. The differential spectra show that higher partial waves represent the majority of the pp → ppφ total cross section at an excess energy of 76 MeV, whose energy dependence would then seem to require some s-wave φp enhancement near threshold. The non-φ data can be described in terms of the combined effects of two-body final state interactions using the same effective scattering parameters determined from lower energy data.

The legacy of the experimental hadron physics programme at COSY

“…The larger acceptance available at the ANKE spectrometer allowed experiments to be carried out at higher excess energies, including above the φ threshold. The higher statistics also meant that more differential observables could be usefully measured [260,261,262,263].…”

“…The experimental procedure was somewhat different at ANKE [260,261,262,263], where the K + candidate was first selected using time-of-flight information 5 . The signal from the K + stop counter was then used in the determination of the momenta of the K − and one of the protons.…”

“…It was first apparent in the COSY-11 data at Q = 10 and 28 MeV [258] that the K − p interaction was strongly attractive because the measured events clustered around low K − p or even low K − pp invariant masses. This observation was taken up by the ANKE collaboration [261,262,263] which, following COSY-11, constructed the ratios of cross sections with respect to the K ± p and K ± pp invariant masses:…”

Measurement of the Strong Interaction Induced Shift and Width of the 1$s$ State of Kaonic Deuterium at J-PARC

“…Techniques such as scattering experiments and X-ray spectroscopy of kaonic atoms [1] as well as production experiments close to threshold [2][3][4][5][6][7] have been used over many years. Theoretical investigations based on the experimental results have also been performed [8][9][10][11][12][13][14][15][16][17][18][19].…”

Strong interaction between kaons in the reactions e+e−→K+KLeśniak1, Sobczuk2, Silarski3 et al. 2018Phys. Rev. D0000View full textAdd to dashboardCite

“…This type of studies was conducted, for example, in the pp → ppK + K − reaction at the COSY synchrotron in Jülich, Germany. However, small cross sections and the presence of strongly interacting protons in the final state, made it impossible to accurately estimate the scattering length of the K + K − interaction [10][11][12]. Thus, it seems that it is much better to study less complicated final states produced, for example, in heavy meson decays J/ψ → φK + K − [13], B 0 s → J/ψf 0 (980) [14] or in the e + e − → K + K − γ and e + e − → K 0K 0 γ reactions.…”