标题：Remote coronal dimmings related to a circular-ribbon flare
作者：Zhang, Q. M.; Zheng, R. S.
作者机构：[Zhang, Q. M.] Chinese Acad Sci, Key Lab Dark Matter & Space Sci, Purple Mt Observ, Nanjing 210033, Peoples R China.; [Zhang, Q. M.] Macau Univ Sci 更多
通讯作者：Zhang, QM;Zhang, QM;Zhang, QM
通讯作者地址：[Zhang, QM]Chinese Acad Sci, Key Lab Dark Matter & Space Sci, Purple Mt Observ, Nanjing 210033, Peoples R China;[Zhang, QM]Macau Univ Sci & Technol, S 更多
来源：ASTRONOMY & ASTROPHYSICS
关键词：Sun: corona; Sun: flares; Sun: filaments, prominences; Sun: magnetic; fields
摘要：Aims. In this paper, we report multiwavelength observations of remote coronal dimmings related to an M1.1 circular-ribbon flare in active region (AR) 12434.; Methods. The confined flare without a coronal mass ejection was observed by the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory on 2015 October 16. We obtained global three-dimensional (3D) magnetic fields before the flare using the potential field source surface modeling.; Results. A few minutes before the flare hard X-ray peak time (06:13:48 UT), small-scale, weak dimming appeared similar to 240 '' away from the flare site, which can be observed by AIA only in 131 and 171 angstrom. Afterward, long and narrow dimmings became evident in all AIA extreme-ultraviolet passbands except 304 angstrom, while localized core dimming was not clearly observed near the flare site. The large-area dimmings extended southeastward and the areas increased gradually. The total area of dimmings reaches (1.2 +/- 0.4) x 10(4) Mm(2) in 193 angstrom. The maximal relative intensity decreases in 171 and 193 angstrom reach 90% and 80%, respectively. Subsequently, the dimmings began to replenish and the area decreased slowly, lasting for >= 3 h. The remote dimmings and AR 12434 are connected by large-scale coronal loops. The remote dimmings are associated with the southwest footpoints of coronal loops with weak negative polarities. Possible origins of remote dimmings are discussed.