立方衛星的發展大大降低了太空任務的門檻，使得建造太空儀器變得更加容易實現。由立方衛星組成的衛星群可以測量一些太空事件的幾何特徵，例如地面伽馬射線閃光和短伽馬射線爆。立方衛星群的測量結果還可以與其他項目的探測器結合進行同步觀測。立方衛星群測量的解析度也高於單一探測裝置的測量解析度。

我們自行開發了用於伽瑪射線瞬變事件觀測的伽瑪射線偵測器(Gamma-ray Detector Monitor, GDM)。它由四個LYSO-SiPM單元和六個BC408-SiPM單元組成。LYSO因其高密度和短衰減時間而被選用於伽馬射線觀測。我們使用鈉-22驗證了LYSO的伽馬射線可探測性，並使用GEANT4模擬分析了GDM的性能。為了開發可靠的立方衛星，我們與成公大學機械工程學系陳重德教授的團隊合作進行結構設計和機械測試。我們也使用GMAT模擬來估計立方衛星群的任務持續時間。在這篇論文中，我將展示GDM和立方衛星結構的設計細節。

Due to the developement of CubeSat, building a space instrument is more achievable and affordable. A constellation constructed by CubeSat can measure the geometric characteristics of some space events such as Terrestrial Gamma-ray Flash (TGF) and short Gamma-Ray Burst (short GRB). And the measurement results from constellation can also be combined with simultaneously collected data from other projects. The resolution of measurement by constellation is also higher than that of single detection devices.

We develope a Gamma-ray Detector Monitor (GDM) for the gamma-ray transient event observation by our self. It consists of four LYSO-SiPM units and six BC408-SiPM units. LYSO is chosen for gamma ray observation due to its high density and short decay time. We varified the gamma ray detectability of LYSO using Na22 and analyzed the performance of GDM with GEANT4 simulation. To develop a reliable CubeSat, we collaborated with Professor Chung-De Chen's group from NCKU Department of Mechanical Engineering for structure design and mechanical testing. We also estimated the mission duration of CubeSat constellation using GMAT simulation. In this thesis, I will demonstrate the detail design and performance of GDM and CubeSat structure.

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