J. Smyrski

COSY- 11, an internal experimental facility for threshold measurements

Abstract The COSY-11 installation is an internal experiment at the cooler synchrotron and storage ring COSY Julich. It has been designed for full geometrical acceptance close to threshold for meson production studies, especially in the 1 GeV/ c 2 mass range. The experimental setup makes use of a regular C-type COSY dipole magnet, following a cluster target, to separate reaction products from the beam and to analyze their momenta, thus allowing the observation of charged reaction products at small angles with beam energies close to threshold. Resonances will be identified by missing mass reconstructions from measured four-momenta of two outgoing protons in the predominantly studied pp → ppX reaction. In addition, charged mesons either produced directly or from decays of X will be detected. The different components of the experimental facility are presented.

ETA ' PRODUCTION IN PROTON-PROTON SCATTERING CLOSE TO THRESHOLD

The

S-wave η′-proton FSI; phenomenological analysis of near-threshold production of π0, η, and η′ mesons in proton-proton collisions

pp \to pp \eta^{\prime}

Photoproduction of η′-mesons with the 4π-detector SAPHIR

(958) reaction has been measured at COSY using the internal beam and the COSY-11 facility. The total cross sections at the four different excess energies \mbox{

Near-threshold η meson production in proton-proton collisions

Q = ~1.5 ~MeV, ~1.7 ~MeV, ~2.9 ~MeV,

Comparison of Lambda and Sigma**0 threshold production in proton proton collisions

and

A novel method for the line-of-response and time-of-flight reconstruction in TOF-PET detectors based on a library of synchronized model signals

~4.1 MeV

Test of a single module of the J-PET scanner based on plastic scintillators

} have been evaluated to be \mbox{

Energy dependence of the near-threshold total cross-section for the pp→ppη′ reaction

\sigma = 2.5 \pm 0.5~nb

Near threshold eta meson production in proton proton collisions

,