The Square Kilometre Array(SKA)is the largest radio interferometer under construction in the world.Its immense amount of visibility data poses a considerable challenge to the subsequent processing by the science data ...The Square Kilometre Array(SKA)is the largest radio interferometer under construction in the world.Its immense amount of visibility data poses a considerable challenge to the subsequent processing by the science data processor(SDP).Baseline dependent averaging(BDA),which reduces the amount of visibility data based on the baseline distribution of the radio interferometer,has become a focus of SKA SDP development.This paper developed and implemented a full-featured BDA module based on Radio Astronomy Simulation,Calibration and Imaging Library(RASCIL).Simulated observations were then performed with RASCIL based on a full-scale SKA1-LOW configuration.The performance of the BDA was systematically investigated and evaluated based on the simulated data.The experimental results confirmed that the amount of visibility data is reduced by about 50%to 85%for different time intervals(Δt_(max)).In addition,differentΔt_(max)have a significant effect on the imaging quality.The smallerΔt_(max)is,the smaller the degradation of imaging quality.展开更多
基金supported by the National SKA Program of China(2020SKA0110300)the Joint Research Fund in Astronomy(U1831204,U1931141)under cooperative agreement between the National Natural Science Foundation of China(NSFC)and the Chinese Academy of Sciences(CAS)+3 种基金the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China(11961141001)the National Science Foundation for Young Scholars(11903009)supported by the Astronomical Big Data Joint Research Centerco-founded by National Astronomical Observatories,Chinese Academy of Sciences and Alibaba Cloud。
文摘The Square Kilometre Array(SKA)is the largest radio interferometer under construction in the world.Its immense amount of visibility data poses a considerable challenge to the subsequent processing by the science data processor(SDP).Baseline dependent averaging(BDA),which reduces the amount of visibility data based on the baseline distribution of the radio interferometer,has become a focus of SKA SDP development.This paper developed and implemented a full-featured BDA module based on Radio Astronomy Simulation,Calibration and Imaging Library(RASCIL).Simulated observations were then performed with RASCIL based on a full-scale SKA1-LOW configuration.The performance of the BDA was systematically investigated and evaluated based on the simulated data.The experimental results confirmed that the amount of visibility data is reduced by about 50%to 85%for different time intervals(Δt_(max)).In addition,differentΔt_(max)have a significant effect on the imaging quality.The smallerΔt_(max)is,the smaller the degradation of imaging quality.
