Design and performance study of the HEPP-H calorimeter onboard the CSES satellite

The China Seismo-Electromagnetic Satellite(CSES) will investigate iono-magnetospheric disturbance and will monitor the temporal stability of the inner Van Allen radiation belts.In particular,the mission aims at confirming the existences of a temporal correlation between the occurrence of earthquakes and the observation of electromagnetic disturbances, plasma fluctuations and anomalous fluxes of high-energy particles precipitating from the inner Van Allen belt in space.The high energy detector of the High Energy Particle Package(HEPP-H) is a payload onboard CSES and is designed for detecting electrons(2–50 MeV) and protons(20–200 MeV) in its 500 km orbit above Earth.CSES was launched in February 2018.In this paper, the instrumentation and development of the HEPP-H calorimeter are described.The calibration with beam particles(electrons and protons) is discussed in detail.

The development and application of the test system for the silicon pixel modules in HEPS-BPIX

Background HEPS-BPIX is a prototype of photon counting pixel detector developed for the High Energy Photon Source.It consists of 16 silicon pixel modules which should be tested individually to ensure the function and performance.Purpose Due to various factors such as the non-uniformity of the processes and voltage drop,the response of each pixel in the silicon pixel module is not identical completely.The response difference of pixels can be minimized by the threshold calibration.This system is developed for the quality test and calibration of the silicon pixel modules.Methods The system consists of a mother board,a control board and a data acquisition(DAQ)system.The mother board provides necessary resources including power supplies and the fanout of calibration signals.Besides,it can be used to test the connectivity by monitoring the power states.The control board reads data out and provides the clock,trigger and configuration data for the silicon pixel module.The DAQ system sends the control commands and receives the readout data through an Ethernet link.Results Compared with the previous readout system,this designed system has a lower noise level and better scanning curves making the calibration more accurate.And it has been successfully applied to the comparison experiments of the through silicon via and wire-bonding silicon pixel modules.Conclusion The results show that this test system can be used to the quality test and calibration of the silicon pixel modules.In addition,the system can be adapted to the measurement of different pixel array detector modules.

FPGA implementation of 10 G Ethernet-based DAQ systems for pixel detectors

Background High Energy Photon Source-Test Facility is a project to study and verify the feasibility of the key technologies which will be applied to that of High Energy Photon Source(HEPS).The pixel array detector is one of the most important components of synchrotron radiation detection.Purpose In order to meet the requirements of the X-ray detection of HEPS,it was asked to independently develop a pixel array detector prototype with an effective detection area larger than 8×8 cm^(2),a spatial resolution better than 200 pm,a detectable energy range from 8 to 20 keV,and a frame rate higher than 1 kHz.The readout electronics system using the field-programmable gate array(FPGA)as its core of the digital logic makes the basic functions of the detector prototype feasibility by implementing all the configuration and data readout of the BPIX which is the dedicated pixel readout chip designed for Chinese next generation of synchrotron light source and working in the single-photon counting mode.Considering the large amount of data generated by pixel detectors and the demand for real-time data acquisition at higher frame rates,a firmware based on the TCP/IP protocol was developed in FPGA.Methods The implementation of 1 G/10 G Ethernet hub firmware provides a method of processing multi-ports Gigabit data and improving bandwidth.The key idea is the conversion of the GMII/XGMII bus in 1 G/10 G Ethernet protocol and the Arbitrator module applying Round-Robin algorithms.Results and conclusion The firmware converts and gathers TCP/IP frames from Gigabit network to 10-Gigabit network successfully.Through measurement,the bandwidth of the hub can reach 8.57 Gbps.A pixel detector integrated with 1 G/10 G Ethernet hub completes the readout of large flux data on 1.5 mega pixels detector at 1.2 kHz frame rate.