1 Abstract A detector setup for the cooler storage ring CELSIUS is described. The setup detects particles produced in interactions between the internal beam and a gas jet target. Particles emitted in the forward direction are measured by means of arrays of plastic scintillators and proportional counters. Particles, particularly photons, emitted more… (More)
Exclusive measurements of the production of-mesons in the pp ! ppp reaction have been carried out at excess energies of 16 and 37 MeV above threshold. The deviations from phase space are dominated by the proton-proton nal state interaction and this innuences particularly the energy distribution of the meson. However, evidence is also presented at the higher… (More)
The rst measurement of the quasi-free p+n!p+n+ reaction cross section has been made at the CELSIUS storage ring using a deuterium internal cluster jet target. The energy dependence of the cross section is extracted using a xed incident proton energy of T p = 1350 MeV and exploiting the Fermi momentum of the struck neutron. The data cover a range of… (More)
The WASA 4π multidetector system, aimed at investigating light meson production in light ion collisions and η meson rare decays at the CELSIUS storage ring in Uppsala is presented. A detailed description of the design, together with the anticipated and achieved performance parameters are given.
The quasi-free p+n!d+ reaction cross section has been measured in the near-threshold region using deuterium from an internal cluster-jet target and 1350 MeV protons in the CELSIUS storage ring. The energy dependence of the cross section is extracted by reconstructing the kinematics on an event-by-event basis and exploiting the Fermi momentum of the target… (More)
The pp-->pp pi(+) pi(-) reaction has been measured exclusively near threshold at CELSIUS. The total cross sections are nearly an order of magnitude lower than expected from previous inclusive measurements. The differential cross sections reveal pp-->pp(*)(1440)-->pp sigma = pp(pi(+)pi(-))(I = l = 0) as the dominant process as well as significant… (More)