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arXiv · 2505.10995

Recurrent Jetlets Associated with the Disappearance of a Satellite Spot

Liheng Yang·Xiaoli Yan·Jun Zhang·Zhike Xue·Zhe Xu·Jincheng Wang·Yijun Hou·Yian Zhou·Defang Kong·Roslan Umar·Xinsheng Zhang·Qiaoling Li·Liping Yang
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Abstract

Recurrent small-scale eruptions are fascinating phenomena in the solar atmosphere. However, their underlying physical mechanisms remain unclear. On 2021 May 23, five recurrent jetlets (J1-J5) were observed continuously ejecting from a satellite spot located at the north edge of AR 12824. Using high-resolution, multi-wavelength data from NVST, SDO, and IRIS, we investigate the physical characteristics of these jetlets and their relationship with the satellite spot. The widths of these jetlets range from 1300 to 2900 km, their lifetimes range span 3 to 10 minutes, and their projection speeds vary from 152.8 to 406.0 km s$^{-1}$. During the eruptions, the satellite spot moved northwest at a low speed of 376 $\pm$ 12 m s$^{-1}$. Its area gradually decreased due to magnetic cancellation with surrounding positive magnetic field, resulting in an average cancellation rate of 1.3$\times$10$^{18}$ Mx hr$^{-1}$. Dark lanes that separated from the satellite spot and small pores were observed to move toward nearby these features or dark lanes with opposite polarities, eventually disappearing during the magnetic cancellation process. J4 was driven by an eruption of a micro-filament. Spectral observations revealed a redshift on the right side of J4 and a blueshift on the left side of its base, suggesting a counterclockwise rotation. The horizontal magnetic field of the satellite spot consistently exhibited a vortex structure throughout its evolution until it vanished. The nonlinear force-free field extrapolation confirms that the satellite spot serves as one footpoint of a mini-flux rope. These observations reveal that these jetlets might result from three-dimensional null-point magnetic reconnection, initiated by the continuous eruption of a mini-flux-rope or multiple mini-flux-ropes, driven by sustained magnetic cancellation.

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Liheng Yang, Xiaoli Yan, Jun Zhang, Zhike Xue, Zhe Xu, Jincheng Wang, Yijun Hou, Yian Zhou, Defang Kong, Roslan Umar, Xinsheng Zhang, Qiaoling Li, Liping Yang. 2025-05-16. Recurrent Jetlets Associated with the Disappearance of a Satellite Spot. https://arxiv.org/abs/2505.10995

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