Dechao Song, J. Tian, Y. Li, M. Ding, Yang Su, Sijie Yu, Jie Hong, Ye Qiu, S. Rao, Xiaofeng Liu, Qiao-Chu Li, Xingyao Chen, Chuan Li, Cheng Fang
{"title":"一次太阳白光耀斑的光谱观测与模拟","authors":"Dechao Song, J. Tian, Y. Li, M. Ding, Yang Su, Sijie Yu, Jie Hong, Ye Qiu, S. Rao, Xiaofeng Liu, Qiao-Chu Li, Xingyao Chen, Chuan Li, Cheng Fang","doi":"10.3847/2041-8213/ace18c","DOIUrl":null,"url":null,"abstract":"The heating mechanisms of solar white-light flares remain unclear. We present an X1.0 white-light flare on 2022 October 2 (SOL2022-10-02T20:25) observed by the Chinese Hα Solar Explorer that provides two-dimensional spectra in the visible light for the full solar disk with a seeing-free condition. The flare shows a prominent enhancement of ∼40% in the photospheric Fe i line at 6569.2 Å, and the nearby continuum also exhibits a maximum enhancement of ∼40%. For the continuum near the Fe i line at 6173 Å from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, it is enhanced up to ∼20%. At the white-light kernels, the Fe i line at 6569.2 Å has a symmetric Gaussian profile that is still in absorption and the Hα line at 6562.8 Å displays a very broad emission profile with a central reversal plus a red or blue asymmetry. The white-light kernels are cospatial with the microwave footpoint sources observed by the Expanded Owens Valley Solar Array and the time profile of the white-light emission matches that of the hard X-ray emission above 30 keV from the Gamma-ray Burst Monitor (GBM) on Fermi. These facts indicate that the white-light emission is qualitatively related to a nonthermal electron beam. We also perform a radiative hydrodynamic simulation with the electron-beam parameters constrained by the hard X-ray observations from Fermi/GBM. The result reveals that the white-light enhancement cannot be well explained by a pure electron-beam heating together with its induced radiative backwarming but may need additional heating sources such as Alfvén waves.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE\",\"authors\":\"Dechao Song, J. Tian, Y. Li, M. Ding, Yang Su, Sijie Yu, Jie Hong, Ye Qiu, S. Rao, Xiaofeng Liu, Qiao-Chu Li, Xingyao Chen, Chuan Li, Cheng Fang\",\"doi\":\"10.3847/2041-8213/ace18c\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The heating mechanisms of solar white-light flares remain unclear. We present an X1.0 white-light flare on 2022 October 2 (SOL2022-10-02T20:25) observed by the Chinese Hα Solar Explorer that provides two-dimensional spectra in the visible light for the full solar disk with a seeing-free condition. The flare shows a prominent enhancement of ∼40% in the photospheric Fe i line at 6569.2 Å, and the nearby continuum also exhibits a maximum enhancement of ∼40%. For the continuum near the Fe i line at 6173 Å from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, it is enhanced up to ∼20%. At the white-light kernels, the Fe i line at 6569.2 Å has a symmetric Gaussian profile that is still in absorption and the Hα line at 6562.8 Å displays a very broad emission profile with a central reversal plus a red or blue asymmetry. The white-light kernels are cospatial with the microwave footpoint sources observed by the Expanded Owens Valley Solar Array and the time profile of the white-light emission matches that of the hard X-ray emission above 30 keV from the Gamma-ray Burst Monitor (GBM) on Fermi. These facts indicate that the white-light emission is qualitatively related to a nonthermal electron beam. We also perform a radiative hydrodynamic simulation with the electron-beam parameters constrained by the hard X-ray observations from Fermi/GBM. The result reveals that the white-light enhancement cannot be well explained by a pure electron-beam heating together with its induced radiative backwarming but may need additional heating sources such as Alfvén waves.\",\"PeriodicalId\":179976,\"journal\":{\"name\":\"The Astrophysical Journal Letters\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Astrophysical Journal Letters\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3847/2041-8213/ace18c\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Astrophysical Journal Letters","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3847/2041-8213/ace18c","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE
The heating mechanisms of solar white-light flares remain unclear. We present an X1.0 white-light flare on 2022 October 2 (SOL2022-10-02T20:25) observed by the Chinese Hα Solar Explorer that provides two-dimensional spectra in the visible light for the full solar disk with a seeing-free condition. The flare shows a prominent enhancement of ∼40% in the photospheric Fe i line at 6569.2 Å, and the nearby continuum also exhibits a maximum enhancement of ∼40%. For the continuum near the Fe i line at 6173 Å from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, it is enhanced up to ∼20%. At the white-light kernels, the Fe i line at 6569.2 Å has a symmetric Gaussian profile that is still in absorption and the Hα line at 6562.8 Å displays a very broad emission profile with a central reversal plus a red or blue asymmetry. The white-light kernels are cospatial with the microwave footpoint sources observed by the Expanded Owens Valley Solar Array and the time profile of the white-light emission matches that of the hard X-ray emission above 30 keV from the Gamma-ray Burst Monitor (GBM) on Fermi. These facts indicate that the white-light emission is qualitatively related to a nonthermal electron beam. We also perform a radiative hydrodynamic simulation with the electron-beam parameters constrained by the hard X-ray observations from Fermi/GBM. The result reveals that the white-light enhancement cannot be well explained by a pure electron-beam heating together with its induced radiative backwarming but may need additional heating sources such as Alfvén waves.