EXTRAPOLATION OF THE SOLAR CORONAL MAGNETIC FIELD FROM SDO/HMI MAGNETOGRAM BY A CESE-MHD-NLFFF CODE

	EXTRAPOLATION OF THE SOLAR CORONAL MAGNETIC FIELD FROM SDO/HMI MAGNETOGRAM BY A CESE-MHD-NLFFF CODE
	Jiang, Chaowei; Feng, Xueshang
刊名	ASTROPHYSICAL JOURNAL
	2013-06-01
卷号	769 期号:2 页码:144
关键词	magnetic fields magnetohydrodynamics (MHD) methods: numerical Sun: corona
ISSN号	0004-638X
通讯作者	北京8701信箱
中文摘要	Due to the absence of direct measurement, the magnetic field in the solar corona is usually extrapolated from the photosphere in a numerical way. At the moment, the nonlinear force-free field (NLFFF) model dominates the physical models for field extrapolation in the low corona. Recently, we have developed a new NLFFF model with MHD relaxation to reconstruct the coronal magnetic field. This method is based on CESE–MHD model with the conservation-element/solution-element (CESE) spacetime scheme. In this paper, we report the application of the CESE–MHD–NLFFF code to Solar Dynamics Observatory/Helioseismic and Magnetic Imager (SDO/HMI) data with magnetograms sampled for two active regions (ARs), NOAA AR 11158 and 11283, both of which were very non-potential, producing X-class flares and eruptions. The raw magnetograms are preprocessed to remove the force and then inputted into the extrapolation code. Qualitative comparison of the results with the SDO/AIA images shows that our code can reconstruct magnetic field lines resembling the EUV-observed coronal loops. Most important structures of the ARs are reproduced excellently, like the highly sheared field lines that suspend filaments in AR 11158 and twisted flux rope which corresponds to a sigmoid in AR 11283. Quantitative assessment of the results shows that the force-free constraint is fulfilled very well in the strong-field regions but apparently not that well in the weak-field regions because of data noise and numerical errors in the small currents.
英文摘要	Due to the absence of direct measurement, the magnetic field in the solar corona is usually extrapolated from the photosphere in a numerical way. At the moment, the nonlinear force-free field (NLFFF) model dominates the physical models for field extrapolation in the low corona. Recently, we have developed a new NLFFF model with MHD relaxation to reconstruct the coronal magnetic field. This method is based on CESE-MHD model with the conservation-element/solution-element (CESE) spacetime scheme. In this paper, we report the application of the CESE-MHD-NLFFF code to Solar Dynamics Observatory/Helioseismic and Magnetic Imager (SDO/HMI) data with magnetograms sampled for two active regions (ARs), NOAA AR 11158 and 11283, both of which were very non-potential, producing X-class flares and eruptions. The raw magnetograms are preprocessed to remove the force and then inputted into the extrapolation code. Qualitative comparison of the results with the SDO/AIA images shows that our code can reconstruct magnetic field lines resembling the EUV-observed coronal loops. Most important structures of the ARs are reproduced excellently, like the highly sheared field lines that suspend filaments in AR 11158 and twisted flux rope which corresponds to a sigmoid in AR 11283. Quantitative assessment of the results shows that the force-free constraint is fulfilled very well in the strong-field regions but apparently not that well in the weak-field regions because of data noise and numerical errors in the small currents.
学科主题	空间物理
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	FORCE-FREE FIELDS ; ACTIVE-REGION ; MASS EJECTION ; BOUNDARY DATA ; FLUX ROPES ; RECONSTRUCTION ; ENERGY ; FLARE ; EVOLUTION ; MODEL
收录类别	SCI
语种	英语
WOS记录号	WOS:000319999100060
内容类型	期刊论文
源URL	[http://ir.cssar.ac.cn/handle/122/1491]
专题	国家空间科学中心_空间科学部
作者单位	Chinese Acad Sci, Ctr Space Sci & Appl Res, State Key Lab Space Weather, SIGMA Weather Grp, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Jiang, Chaowei,Feng, Xueshang. EXTRAPOLATION OF THE SOLAR CORONAL MAGNETIC FIELD FROM SDO/HMI MAGNETOGRAM BY A CESE-MHD-NLFFF CODE[J]. ASTROPHYSICAL JOURNAL,2013,769(2):144.
APA	Jiang, Chaowei,&Feng, Xueshang.(2013).EXTRAPOLATION OF THE SOLAR CORONAL MAGNETIC FIELD FROM SDO/HMI MAGNETOGRAM BY A CESE-MHD-NLFFF CODE.ASTROPHYSICAL JOURNAL,769(2),144.
MLA	Jiang, Chaowei,et al."EXTRAPOLATION OF THE SOLAR CORONAL MAGNETIC FIELD FROM SDO/HMI MAGNETOGRAM BY A CESE-MHD-NLFFF CODE".ASTROPHYSICAL JOURNAL 769.2(2013):144.