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Remote coronal dimmings related to a circular-ribbon flare

In this paper, multiwavelength observations of remote coronal dimmings related to an M1.1 circular-ribbon flare (CRF) in active region (AR) 12434 are reported. The confined flare without a CME was observed by AIA and HMI on board SDO on 2015 October 16. Global three-dimensional (3D) magnetic fields before flare were obtained using the potential field source surface modeling. A few minutes before the flare hard X-ray peak time (06:13:48 UT), small-scale, weak dimming appeared $\sim$240$\arcsec$ away from the flare site, which can be observed by AIA only in 131 and 171 Å. Afterwards, long and narrow dimmings became evident in all AIA EUV passbands except 304 Å, 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$\pm0.4$)$\times$10$^4$ Mm$^2$ in 193 Å. The maximal relative intensity decreases in 171 and 193 Å reach 90\% and 80\%, respectively. Subsequently, the dimmings began to replenish and the area decreased slowly, lasting for $\geq$3 hr. The remote dimmings and AR 12434 were connected by large-scale coronal loops. The remote dimmings were associated with the southwest footpoints of coronal loops with weak negative polarities. Possible origins of remote dimmings are discussed.