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In this paper, a novel mechanical structure for a gamma-ray monitor (GRM) is designed for a small satellite payload. Its structural stiffness, strength and dynamic response are directly related to the performance of the novel GRM, which must meet the static and dynamic characteristic requirements of the structure in a harsh vibration environment. The static and dynamic simulation of the structure are carried out by finite element method (FEM), and the mechanical structure response laws of the novel GRM are analyzed and validated by vibration tests. Through comparing the frequency response simulation results with the vibration test results, the minimum safety factor of the key components of the structure is 4.07, the fundamental frequency error is within 5.04%, the acceleration response error is within 8.5%, the root mean square of total acceleration (Grms) error is within 14.2%, and the sinusoidal characteristic sweep frequency error before and after the vibration test is within 5.0%. The results show that the payload structure has large structural stiffness, high strength and reasonable frequency response characteristics, and meets the design requirements.

The thermal structure of the environmental atmosphere associated with Terrestrial Gamma-ray Flashes (TGFs) is investigated with the combined observations from several detectors (FERMI, RHESSI, and Insight-HXMT) and GNSS-RO (SAC-C, COSMIC, GRACE, TerraSAR-X, and MetOp-A). The geographic distributions of TGF-related tropopause altitude and climatology are similar. The regional TGF-related tropopause altitude in Africa and the Caribbean Sea is 0.1–0.4 km lower than the climatology, whereas that in Asia is 0.1–0.2 km higher. Most of the TGF-related tropopause altitudes are slightly higher than the climatology, while some of them have a slightly negative bias. The subtropical TGF-producing thunderstorms are warmer in the troposphere and have a colder and higher tropopause over land than the ocean. There is no significant land–ocean difference in the thermal structure for the tropical TGF-producing thunderstorms. The TGF-producing thunderstorms have a cold anomaly in the middle and upper troposphere and have stronger anomalies than the deep convection found in previous studies.