Transcript Slides
NEC 2015 Trigger module for spectrometer with DT5742 digitizer. O.V. Strekalovsky, D.V. Kamanin, Yu.V. Pyatkov, A.O. Strekalovsky, V.E. Zhuchko LIS spectrometer 252Сf Red – silicon PIN-diodes Yellow – timestamp detectors based on microchannel plates. • Plasma delay – time offset between the track formation and the activation of the time discriminator for fission fragments Pulse height defect – reducing of the pulse amplitude at the output of a PIN detector with fission fragments. Timestamp detectors – fast timestamp without plasma delay LIS spectrometer PIN1 MCP1 St 252Сf MCP2 PIN2 LISSA (Light Ions Spectrometer for South Africa) University of Stellenbosch, Faculty of Military Science, Military Academy, Saldanha, South Africa Actually we mean double armed time-of-flight HI spectrometer based on PIN diodes and micro-channel plates based time pick-of detectors. LISSA is dedicated mainly for the training of the students of different levels including PHD who are specialized in nuclear physics. At the same time after upgrade aimed at increasing of the efficiency it is a real setup for study of the multi-body decays at the HI beams. COMETA - F COMETA setup To study of the multi-body decays of heavy nuclei, for instance, so called collinear cluster tri-partition (CCT) discovered here in the Flerov Lab. Ms=236 amu COMETA setup Really, you need mosaic “stop” detector for independent detection of two almost collinear CCT partners. This detector must provide as well measuring of both E and TOF. Mosaic of PIN diodes will be uncontested choice. Mass-mass distribution from235U(n, f) reaction. Strange lines M1=M2+const COMETA-R setup M2 (amu) Ms=236 amu “Unphysical” prolongation of the lines into the region far above of the mass of the mother system…?! M1 (amu) … after searching structures 25.9.15 25.9.15 There are several steps in calculating the fragment energy based on the digital waveforms: to get one-event waveforms from the TDMS file, to extract a waveform for one PIN diode signal, to detect a zero-level line, to invert and move a signal to a zero level, to localize signal duration, and to calculate the integral. To measure the time-of-flight interval, it was merely possible to subtract the absolute time of the digitized “start” signal from the time of the “stop” signal. Off-line digital constant fraction timing method was used as a time pickoff technique. AD 8561 FT2232H 25.9.15 DAC AD5328 8 buffered 12-bit DACs Resistor string DAC followed by an output buffer amplifier 25.9.15 Conclusions Practical experience with the multichannel 5GS/s Switched Capacitor Waveform Digitizer DT5742 reveals the perfect suitability of such devices for the investigation of nuclear decay. The digitizer makes the following possible, which is crucial for conducting our experiments: - It distinguishes pile-up and noise pulses. - Complete information is stored. - It allows reduction of the installation size, the amount of cabling, power consumption, and cost per channel. - Various digital algorithms can be designed and used with the accumulated data. 25.9.15 NEC 2015 Thank you for the attention 25.9.15 25.9.15 25.9.15 25.9.15