As a dedicated solar radioheliograph,the MingantU SpEctral RadioHeliograph(MUSER)has a maximum baseline of more than 3000 m and a frequency range of 400 MHz–15 GHz.According to the classical radio interferometry theo...As a dedicated solar radioheliograph,the MingantU SpEctral RadioHeliograph(MUSER)has a maximum baseline of more than 3000 m and a frequency range of 400 MHz–15 GHz.According to the classical radio interferometry theory,the non-coplanar baseline effect(i.e.,w-term effect)would be considered and calibrated for such a radio instrument.However,little previous literature made the qualitative or quantitative analyses on w-term effects of solar radioheliograph in-depth.This study proposes a complete quantitative analysis of w-term effects for the MUSER.After a brief introduction of the MUSER,we systematically investigate the baseline variations over a year and analyze the corresponding variations of w-term.We further studied the effects of the w-term in the imaging for the specified extended source,i.e.,the Sun.We discussed the possible effects of the w-term,such as image distortion and so on.The simulated results show that the w-term is an essential and unavoidable issue for solar radio imaging with high spatial resolution.展开更多
基金supported by the National SKA Program of China(2020SKA0110300)the Joint Research Fund in Astronomy(U1831204 and U1931141)+3 种基金the National Natural Science Foundation of China(NSFC)the Chinese Academy of Sciences(CAS)the Funds for International Cooperation and Exchange of the NSFC(11961141001)the NSFC(Grant No.11903009)。
文摘As a dedicated solar radioheliograph,the MingantU SpEctral RadioHeliograph(MUSER)has a maximum baseline of more than 3000 m and a frequency range of 400 MHz–15 GHz.According to the classical radio interferometry theory,the non-coplanar baseline effect(i.e.,w-term effect)would be considered and calibrated for such a radio instrument.However,little previous literature made the qualitative or quantitative analyses on w-term effects of solar radioheliograph in-depth.This study proposes a complete quantitative analysis of w-term effects for the MUSER.After a brief introduction of the MUSER,we systematically investigate the baseline variations over a year and analyze the corresponding variations of w-term.We further studied the effects of the w-term in the imaging for the specified extended source,i.e.,the Sun.We discussed the possible effects of the w-term,such as image distortion and so on.The simulated results show that the w-term is an essential and unavoidable issue for solar radio imaging with high spatial resolution.
