Ke Gong

The Silicon Charge Detector (SCD) is a subdetector of the High Energy Cosmic Radiation Detection payload. The dynamic range of the silicon microstrip detector can be extended by the capacitive coupling effect, which is related to the interstrip capacitance and the coupling capacitance. A detector prototype with several sets of parameters was designed and tested in the ion beams at the CERN Super Proton Synchrotron. The capacitive coupling fractions with readout strip and floating strip incidences were studied using the beam test data and SPICE simulation.

As a new member of the Gravitational-wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) after GECAM-A and GECAM-B, GECAM-C (originally called HEBS), which was launched on board the SATech-01 satellite on 2022 July 27, aims to monitor and localize X-ray and gamma-ray transients from ∼6 keV to 6 MeV. GECAM-C utilizes a similar design to GECAM but operates in a more complex orbital environment. In this work, we utilize the secondary particles simultaneously produced by the cosmic-ray events on orbit and recorded by multiple detectors to calibrate the relative timing accuracy between all detectors of GECAM-C. We find the result is 0.1 μs, which is the highest time resolution among all GRB detectors ever flown and very helpful in timing analyses such as minimum variable timescale and spectral lags, as well as in time delay localization. Besides this, we calibrate the absolute time accuracy using the one-year Crab Pulsar data observed by GECAM-C and Fermi’s Gamma-ray Burst Monitor, as well as GECAM-C and GECAM-B. The results are 2.02 ± 2.26 μs and 5.82 ± 3.59 μs, respectively. Finally, we investigate the spectral lag between the different energy bands of the Crab Pulsar observed by GECAM and the Gamma-ray Burst Monitor, which is ∼ −0.2 μs keV⁻¹.

As the main detector of the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor mission (GECAM), the calibration of the energy response and detection efficiency of the gamma-ray detector (GRD) is the main content of the ground-based calibration. This article mainly focuses on the calibration of the energy response and detection efficiency in the 8–160 keV with a refined measurement around the absorption edges of the lanthanum bromide crystal ($\rm {LaBr_3}$). The GRD performances for different crystal types, data acquisition modes, working modes, and incident positions are also analysed in detail. We show that the calibration campaign is comprehensive, the detector performance meets the flight requirements, and the calibration results generally agree with simulations as expected. The detector’s model was corrected by the ground-based calibration, which led to the establishment of the calibration data base.