Grant No MNiSW/NCN DPN/N108/GSI/2009
KRATTA (KRAków Triple Telescope Array) is a modular, low threshold, broad energy range system built to measure the energy, emission angle, and isotopic composition of light charged reaction products. It consists of 38 independent modules which can be arranged in an arbitrary configuration. A single module, covering actively about 4.5 msr of the solid angle at the optimal distance of 40 cm from the target, consists of three identical, thick, large area photodiodes, used also for direct detection, and of two CsI(1500 ppm Tl) crystals of 2.5 and 12.5 cm length, respectively.
All the signals are digitally processed. The lower identification threshold, due to the thickness of the first photodiode, has been reduced to about 2.5 MeV for protons (of Si equivalent) by applying a pulse shape analysis. The pulse shape analysis allowed also to decompose the complex signals from the middle photodiode into their ionization and scintillation components and to obtain a satisfactory isotopic resolution with a single readout channel. The upper energy limit for protons is about 260 MeV. The whole setup is easily portable.
KRATTA detector performed very well during the ASY-EOS experiment (Au+Au collisions at 400 MeV/nucleon), conducted in May 2011 at GSI. It was also applied in several \(p+X \rightarrow X + p + \gamma\) experiments carried out in the Bronowice Cyclotron Center in cooperation with NZ22 Department..
