R. Joosten

High resolution study of the Λp final state interaction in the reaction p+p→K++(Λp)

The reaction pp ! K + + (�p) was measured at Tp = 1.953 GeV and � = 0 ◦ with a high missing mass resolution in order to study thep final state interaction. The large final state enhancement near thep threshold can be described using the stan- dard Jost-function approach. The singlet and triplet scattering lengths and effective ranges are deduced by fitting simultaneously thep invariant mass spectrum and the total cross section data of the freep scattering.

Observation of η′ and φ meson production very close to threshold in the p d → 3He X reaction

Abstract The production of η′ (958) and φ (1020) mesons has been studied very close to threshold in the inclusive p d → 3 He X reaction. The complicated phase space acceptance problem caused by rapidly changing kinematics close to threshold has been carefully treated. The measured averaged squared amplitudes |f|2 at threshold are 0.9 and 2.4 nb/sr for the η′ and φ meso Our results are in remarkable agreement with predictions of a two-step model, which uses existing π− p → n X data as input. However the ratio of φ to ω production seems at variance with naive expectations based on the Okubo-Zweig-Iizuka rule.

Pattern recognition and PID for COMPASS RICH-1

Abstract A package for pattern recognition and PID by COMPASS RICH-1 has been developed and used for the analysis of COMPASS data collected in the years 2002–2004, and 2006–2007 with the upgraded RICH-1 photon detectors. It has allowed the full characterization of the detector in the starting version and in the upgraded one as well as the PID for physics results. We report about the package structure and algorithms, and the detector characterization and PID results.

Experimental study of the pd -> He-3 K+K- and pd -> He-3 phi reactions close to threshold

Two--kaon production in proton--deuteron collisions has been studied at three energies close to threshold using a calibrated magnetic spectrograph to measure the final

Upper limits for a narrow resonance in the reaction p + p to K^++ (Lambda p)

^3

The fast readout system for the MAPMTs of COMPASS RICH-1

He and a vertex detector to measure the

Study of the

K^+K^-

pd\to ^3\textrm{He} K^+K^-

pair. Differential and total cross sections are presented for the production of

and

\phi

pd\to ^3\textrm{He} \phi

--mesons, decaying through