Abstract:
The dark matter particle explorer (DAMPE) is the first launched satellite in our series of space science satellites, which mainly aims at searching for dark matter particles in space. The DAMPE implements precise charge measurement for cosmic-ray ions and identification of high energy e/γ. The plastic scintillator detector (PSD) is a major component in the payload of the DAMPE. The PSD consists of 82 plastic scintillator crystal bars and 164 PMTs (photomultiplier tubes). The dynamic range for each crystal bar is 2×10
3 and in total there are 328 readout channels. These readout channels are read by a complex readout electronic system, which contains 4 front-end electronics (FEE) boards with a total 360 signal processing channels and power consumption of 6 W. The FEE board mainly includes charge measurement circuit, analog conditioning circuit, ADC circuit, calibration circuit, environmental monitoring circuit, FPGA circuit, power management circuit, interface circuit, etc. Its main function is importing the charge of PMT signals to VA160 ASIC based on the 32 channels. To assure the long-term reliability in harsh space environment, several critical issues such as the radiation hardness, thermal design, etc., are taken into consideration. Test results show that the FEE performs well and operates stably. Each electronics channel achieves a dynamic range of 0 to 12.5 pC with a low noise less than 2 fC. The nonlinearity of each channel is less than 0.6% in full dynamic range. The FEE can stand with the harsh space environments and operate in a reliable manner. In 2014 and 2015, the FEE, combined with the PSD, was successfully tested two times at the PS and SPS terminals of CERN. The detection capability of PSD was validated, which can satisfy the function and performance requirements given in project document, and meet actual scientific mission needs.