The Chinese Hα Solar Explorer(CHASE), dubbed “Xihe”—Goddess of the Sun, was launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission is designed...The Chinese Hα Solar Explorer(CHASE), dubbed “Xihe”—Goddess of the Sun, was launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission is designed to test a newly developed satellite platform and to acquire the spectroscopic observations in the Hα waveband. The Hα Imaging Spectrograph(HIS)is the scientific payload of the CHASE satellite. It consists of two observational modes: raster scanning mode and continuum imaging mode. The raster scanning mode obtains full-Sun or region-of-interest spectral images from 6559.7 to 6565.9 ? and from 6567.8 to 6570.6 ? with 0.024 ? pixel spectral resolution and 1 min temporal resolution. The continuum imaging mode obtains photospheric images in continuum around 6689 ? with the full width at half maximum of 13.4 ?. The CHASE mission will advance our understanding of the dynamics of solar activity in the photosphere and chromosphere. In this paper, we present an overview of the CHASE mission including the scientific objectives, HIS instrument overview, data calibration flow, and first results of on-orbit observations.展开更多
The Hα line is an important optical line in solar observations containing the information from the photosphere to the chromosphere. To study the mechanisms of solar eruptions and the plasma dynamics in the lower atmo...The Hα line is an important optical line in solar observations containing the information from the photosphere to the chromosphere. To study the mechanisms of solar eruptions and the plasma dynamics in the lower atmosphere, the Chinese Hα Solar Explorer(CHASE) was launched into a Sun-synchronous orbit on October 14, 2021. The scientific payload of the CHASE satellite is the Hα Imaging Spectrograph(HIS). The CHASE/HIS acquires, for the first time, seeing-free Hα spectroscopic observations with high spectral and temporal resolutions. It consists of two observational modes. The raster scanning mode provides full-Sun or region-of-interest spectra at Hα(6559.7-6565.9 ?) and Fe I(6567.8-6570.6 ?) wavebands. The continuum imaging mode obtains full-Sun photospheric images at around 6689 ?. In this paper, we present detailed calibration procedures for the CHASE/HIS science data, including the dark-field and flat-field correction, slit image curvature correction, wavelength and intensity calibration, and coordinate transformation. The higher-level data products can be directly used for scientific research.展开更多
The Chinese Hα Solar Explorer(CHASE) was successfully launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission, dubbed “Xihe” in Chinese(Goddess ...The Chinese Hα Solar Explorer(CHASE) was successfully launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission, dubbed “Xihe” in Chinese(Goddess of the Sun), is designed to test a newly developed satellite platform and to spectroscopically observe the Sun at the Hα line, which is one of the most important optical lines reflecting the dynamics of solar activities in the lower atmosphere.展开更多
Coronal mass ejections(CMEs)are large-scale explosions of the coronal magnetic field.It is believed that magnetic reconnection significantly builds up the core structure of CMEs,a magnetic flux rope,during the eruptio...Coronal mass ejections(CMEs)are large-scale explosions of the coronal magnetic field.It is believed that magnetic reconnection significantly builds up the core structure of CMEs,a magnetic flux rope,during the eruption.However,the quantitative evolution of the flux rope,particularly its toroidal flux,is still unclear.In this paper,we study the evolution of the toroidal flux of the CME flux rope for four events.The toroidal flux is estimated as the magnetic flux in the footpoint region of the flux rope,which is identified by a method that simultaneously takes the coronal dimming and the hook of the flare ribbon into account.We find that the toroidal flux of the CME flux rope for all four events shows a two-phase evolution:a rapid increasing phase followed by a decreasing phase.We further compare the evolution of the toroidal flux with that of the Geostationary Operational Environmental Satellites soft X-ray flux and find that they are basically synchronous in time,except that the peak of the former is somewhat delayed.The results suggest that the toroidal flux of the CME flux rope may be first quickly built up by the reconnection mainly taking place in the sheared overlying field and then reduced by the reconnection among the twisted field lines within the flux rope,as enlightened by a recent 3D magnetohydrodynamic simulation of CMEs.展开更多
基金supported by China National Space Administration(CNSA)。
文摘The Chinese Hα Solar Explorer(CHASE), dubbed “Xihe”—Goddess of the Sun, was launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission is designed to test a newly developed satellite platform and to acquire the spectroscopic observations in the Hα waveband. The Hα Imaging Spectrograph(HIS)is the scientific payload of the CHASE satellite. It consists of two observational modes: raster scanning mode and continuum imaging mode. The raster scanning mode obtains full-Sun or region-of-interest spectral images from 6559.7 to 6565.9 ? and from 6567.8 to 6570.6 ? with 0.024 ? pixel spectral resolution and 1 min temporal resolution. The continuum imaging mode obtains photospheric images in continuum around 6689 ? with the full width at half maximum of 13.4 ?. The CHASE mission will advance our understanding of the dynamics of solar activity in the photosphere and chromosphere. In this paper, we present an overview of the CHASE mission including the scientific objectives, HIS instrument overview, data calibration flow, and first results of on-orbit observations.
基金supported by China National Space Administration。
文摘The Hα line is an important optical line in solar observations containing the information from the photosphere to the chromosphere. To study the mechanisms of solar eruptions and the plasma dynamics in the lower atmosphere, the Chinese Hα Solar Explorer(CHASE) was launched into a Sun-synchronous orbit on October 14, 2021. The scientific payload of the CHASE satellite is the Hα Imaging Spectrograph(HIS). The CHASE/HIS acquires, for the first time, seeing-free Hα spectroscopic observations with high spectral and temporal resolutions. It consists of two observational modes. The raster scanning mode provides full-Sun or region-of-interest spectra at Hα(6559.7-6565.9 ?) and Fe I(6567.8-6570.6 ?) wavebands. The continuum imaging mode obtains full-Sun photospheric images at around 6689 ?. In this paper, we present detailed calibration procedures for the CHASE/HIS science data, including the dark-field and flat-field correction, slit image curvature correction, wavelength and intensity calibration, and coordinate transformation. The higher-level data products can be directly used for scientific research.
文摘The Chinese Hα Solar Explorer(CHASE) was successfully launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission, dubbed “Xihe” in Chinese(Goddess of the Sun), is designed to test a newly developed satellite platform and to spectroscopically observe the Sun at the Hα line, which is one of the most important optical lines reflecting the dynamics of solar activities in the lower atmosphere.
基金funded by NSFC grants 11722325,11733003,11790303,and 11790300Jiangsu NSF grant BK20170011the Dengfeng B program of Nanjing University.
文摘Coronal mass ejections(CMEs)are large-scale explosions of the coronal magnetic field.It is believed that magnetic reconnection significantly builds up the core structure of CMEs,a magnetic flux rope,during the eruption.However,the quantitative evolution of the flux rope,particularly its toroidal flux,is still unclear.In this paper,we study the evolution of the toroidal flux of the CME flux rope for four events.The toroidal flux is estimated as the magnetic flux in the footpoint region of the flux rope,which is identified by a method that simultaneously takes the coronal dimming and the hook of the flare ribbon into account.We find that the toroidal flux of the CME flux rope for all four events shows a two-phase evolution:a rapid increasing phase followed by a decreasing phase.We further compare the evolution of the toroidal flux with that of the Geostationary Operational Environmental Satellites soft X-ray flux and find that they are basically synchronous in time,except that the peak of the former is somewhat delayed.The results suggest that the toroidal flux of the CME flux rope may be first quickly built up by the reconnection mainly taking place in the sheared overlying field and then reduced by the reconnection among the twisted field lines within the flux rope,as enlightened by a recent 3D magnetohydrodynamic simulation of CMEs.
