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LaBr3:Ce,CeBr3 and GAGG:Ce scintillators were investigated and the determined characteristics were compared with those obtained for the well-known and widely used CsI:Tl and NaI:Tl crystals. All the detectors were of the same size of 10 × 10 × 5 mm3. The aim of this test study was to single out scintillation detectors most suitable for γ-ray spectrometry and γ-ray emission radial profile measurements in high-temperature plasma experiments. Decay time, energy resolution, non-proportionality and full energy peak detection efficiency ere measured for γ-ray energies up to 1770 keV. Due to their good energy resolution, short decay time and high detection efficiency for MeV gamma rays, LaBr3:Ce and CeBr3 scintillators are proposed as the best candidates for use especially under conditions of high count rates, which are expected in the forthcoming DT experiments.

Basic concepts and the development of a high counting rate digital spectrometry system based on efficient ADCs and latest available FPGA are presented with the aim of using such a system, coupled to fast scintillators, in plasma experiments. The prototype system is a 1 channel 12-bit 1 GSPS digitizer with 2~\mathrm V\mathrm {pp} input voltage. Preliminary results tested with different radioactive sources are shown for low (0.03 Mcps) and high (2.2 Mcps) counting rates. A comparison of energy spectra and energy resolution with what obtained by a commercial device is also shown. [ABSTRACT FROM PUBLISHER]

Excited neutral hyperons Y0* produced in the pp → pK+Y0* reaction with a COSY beam momentum of 3.65 MeV/c have masses below 1540 MeV/c2. The ANKE spectrometer allows the simultaneous observation of different decay modes: Y0* → π0Σ0, π∓Σ±, π0Λ, K-p by measuring kaons and pions of either charge in coincidence with protons. We have found indications for a neutral excited hyperon resonance Y0* with a mass of M(Y0*) = (1480 ± 15) MeV/c2 and a width of Γ(Y0*) = (60±15) MeV/c2. The cross section for Y0* is of the order of few hundred nanobarns. It can be either a Σ0 or a Λ hyperon and on the basis of existing data no conclusion could be made whether it is a three–quark baryon or an exotic state. Missing- and invariant–mass techniques have been used to identify the Λ(1405) resonance decaying via Σ0π0. The cross section for Λ(1405) production is equal to (4.5 ± 0.9stat ± 1.8syst) µb. The shape and position of the Λ(1405) distribution are similar to those found from other decay modes, so no support is given to the two-pole model. [ABSTRACT FROM AUTHOR]