The observation of the low-energyγ-ray(0.1 to 30 MeV)sky has been significantly limited since the COMPTEL instrument aboard the Compton Gamma Ray Observatory(CGRO)satellite was decommissioned in 2000.The exploration...The observation of the low-energyγ-ray(0.1 to 30 MeV)sky has been significantly limited since the COMPTEL instrument aboard the Compton Gamma Ray Observatory(CGRO)satellite was decommissioned in 2000.The exploration ofγ-ray photons within this energy band,often referred to as the MeV gap,is crucial to address numerous unresolved mysteries in high-energy and multi-messenger astrophysics.Although several large MeVγ-ray missions have been proposed(e.g.,e-ASTROGAM,AMEGO,and COSI),most of these are in the planning phase,with launches not expected until the next decade,at the earliest.Recently,there has been a surge in proposed CubeSat missions as cost-effective and rapidly implementable pathfinder alternatives.An MeV CubeSat dedicated toγ-ray astronomy could serve as a valuable demonstrator for large-scale future MeV payloads.This paper proposes aγ-ray payload design with a silicon-based tracker and a cesium iodide-based calorimeter.We report the results of a simulation study to assess the performance of this payload concept and compare the results with those of previousγ-ray instruments.As part of the performance assessment and comparison,we show that with our proposed payload design,a sensitivity better than IBIS can be achieved for energies between 0.1 and 10 MeV,and for energies up to around 1 MeV,the achieved sensitivity is comparable to COMPTEL,therefore opening up a window toward cost-effective observational astronomy with comparable performance to past missions.展开更多
基金supported by HKU-RMGS Funds (207300301 and 207301033principal investigator: Q.A.P.)+1 种基金The research of P.S.P. is partially supported by a General Research Fund (GRF) grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (HKU Project 17304920principal investigator: S. C. Y. Ng).
文摘The observation of the low-energyγ-ray(0.1 to 30 MeV)sky has been significantly limited since the COMPTEL instrument aboard the Compton Gamma Ray Observatory(CGRO)satellite was decommissioned in 2000.The exploration ofγ-ray photons within this energy band,often referred to as the MeV gap,is crucial to address numerous unresolved mysteries in high-energy and multi-messenger astrophysics.Although several large MeVγ-ray missions have been proposed(e.g.,e-ASTROGAM,AMEGO,and COSI),most of these are in the planning phase,with launches not expected until the next decade,at the earliest.Recently,there has been a surge in proposed CubeSat missions as cost-effective and rapidly implementable pathfinder alternatives.An MeV CubeSat dedicated toγ-ray astronomy could serve as a valuable demonstrator for large-scale future MeV payloads.This paper proposes aγ-ray payload design with a silicon-based tracker and a cesium iodide-based calorimeter.We report the results of a simulation study to assess the performance of this payload concept and compare the results with those of previousγ-ray instruments.As part of the performance assessment and comparison,we show that with our proposed payload design,a sensitivity better than IBIS can be achieved for energies between 0.1 and 10 MeV,and for energies up to around 1 MeV,the achieved sensitivity is comparable to COMPTEL,therefore opening up a window toward cost-effective observational astronomy with comparable performance to past missions.