Silicon PIN array-based charge measurement detector for HERD beam test

Purpose The high-energy cosmic radiation detection (HERD) is a dedicated space cosmic ray detector, planned to be launched and installed on the China Space Station (CSS) around 2027. One of the main goals of HERD is to measure the composition and energy spectra of cosmic rays (CR) with energies as high as several PeV by using silicon charge detectors (SCD) (Altomare et al. in The silicon charge detector of the high energy cosmic radiation detection facility, 2023), plastic scintillator detectors (PSD) (Kyratzis et al. in Proceedings of Sc. (ICRC2021), vol. 651, 2021), and 3D calorimeters (CALO) (Liu et al. in J Instrum 18(09):09002, 2023). To assess HERD’s charge measurement capability during the beam test, a particle identification detector (PID) with a large dynamic range is required. Methods A Si-PIN-based PID detector is conceptualized and manufactured. It is composed of four layers, each containing 30 Si-PIN sensors. In four IDE1160 ASICs, the signals from the Si-PIN arrays are preamplified, shaped, peak-held, and serially read out by four IDE1160 ASICs. A DAQ system is created to digitize the analog signals from ASICs, organize the data package, and transfer it to the host computer. Results and conclusion Before going to the beam test, the dynamic range, linearity, pedestal, and noise level of each channel in PID were studied at home. The dynamic range is 0 to +5 pC, the linearity is better than 2%, and the RMSE (Root Mean Square Error) of the pedestal is about 1 fC. The preliminary beam test results show that PID is capable of detecting heavy ions from Z = 4 (Be) to Z = 31 (Ga), and the charge resolution is better than 0.3 charge units (c.u.).