Prototype design of readout electronics for Zero Degree Calorimeter in the HIRFL-CSR external-target experiment

Abstract

A: Located at the center of the end of the CSR External-target Experiment (CEE), the Zero Degree Calorimeter (ZDC) is designed to rebuild the centrality and reaction plane of the nuclear-nuclear collision. To meet the target of ZDC to detect the energy distribution of colliding particles, a high-performance readout system prototype, which implements a Gaussian shaping algorithm, has been designed. The system consists of 4 channels; each channel mainly includes an I-V conversion circuit, a slow forming circuit, a threshold trigger circuit, and a digital signal processing unit based on a field-programmable gate array (FPGA).Performance studies indicate that the noise of each channel is less than 0.8 mV and the nonlinearity is better than 0.6%. Tests with a LED driver source indicate that the Gaussian shaping algorithm can improve the photon energy resolution from 7.481% to 6.196%. Tests with cosmic rays also produced expected results.

The trigger system for the HIRFL-CSR external-target experiment

“…For eTOF and iTOF, the high performance time digitization modules (TDMs) are adopted to obtain high precision timing information [28]. The zero-degree counter (ZDC) [41] is located behind all other detector components and the magnetic field, in order to deliver the information related to the reaction plane and the centrality by measuring the charge-resolved spectators in the very forward region. An active collimator (AC) detector and a silicon pixel (SiPix) detector [42] are installed between the target and T 0 on the beam line to suppress the background events induced by the projectile with upstream materials and to record the vertex of the beam, respectively.…”

Event plane determination from Zero Degree Calorimeter at the Cooling-Storage-Ring External-target Experiment

“…Figure 1(a) shows the sketch of the CEE spectrometer. The detector subsystem consists of: superconducting dipole magnet used to deflect charged particles; Silicon Pixel positioning detector (SiPiX) to measure the position, time of the incident beam, and primary collision vertex [34]; Time Projection Chamber (TPC) to reconstruct the particle trajectory and identify particles [35]; Time-of-flight chamber (TOF) to extend particle identification to high momentum, containing a start-time detector (T0) [36], an inner time-of-flight detector (iTOF) [37], and an end-cap time-of-flight detec-tor (eTOF) [38]; ZDC to measure the pattern (deposited energy and incident position) of forward-going charged particles emitted from nucleus-nucleus collisions [39].…”

Design and characterization of multichannel front-end electronics for detectors at HIRFL and HIAF

“…The heavy ion research facility in Lanzhou (HIRFL) [1] and the high-intensity heavy ion accelerator facility (HIAF) [2] are constructed for researching nuclear physics, quark physics, and heavy ion related applications. Some major experiments performed at HIRFL and HIAF are the internal target facility (ITF) [3], the CSR external-target experiment (CEE) [4], the external target facility (ETF) [5], and the electron-ion collider in China (EICC) [6]. There are many different kinds of detectors in the experiments, and have put forward higher requirements for detector technology.…”