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arXiv · 2312.03571

Observational study of intermittent solar jets: p-mode modulation

Qiuzhuo Cai·Guiping Ruan·Chenxi Zheng·Brigitte Schmieder·Jinhan Guo·Yao Chen·Jiangtao Su·Yang Liu·Jihong Liu·Wenda Cao
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Abstract

Aims. Recurring jets are observed in the solar atmosphere, which can erupt intermittently. By the observation of intermittent jets, we want to understand the causes of periodic eruption characteristics. Methods. We report intermittent jets observed by the GST. The analysis was aided by 1400 Å and 2796 Å data from IRIS.These observational instruments allowed us to analyze the temporal characteristics of jet events. Results. The jet continued for up to 4 hours. The time distance diagram shows that the peak of the jet has obviously periodic eruption characteristics (5 minutes) during 18:00 UT-18:50 UT. We also found periodic brightening phenomenon (5 minutes) during jets bursts in the observed bands in the Transition Region (1400 Å and 2796 Å), which may be a response to intermittent jets in the upper solar atmosphere.The time lag is 3 minutes. Evolutionary images in the TiO band revealed the horizontal movement of granulation at the location of jet. Compared to the quiet region of the Sun, we found that the footpoint of the jet is enhanced at the center of the H α spectral line profile, with no significant changes in the line wings. This suggests the presence of prolonged heating at the footpoint of the jet. In the mixed-polarity magnetic field region of the jet, we observed magnetic flux emergence, cancellation, and shear indicating possible intermittent magnetic reconnection. That is confirmed by the NLFFF model reconstructed using the magneto-friction method. Conclusions. The multi-wavelength analysis indicates that the events we studied were triggered by magnetic reconnection caused by mixed-polarity magnetic fields. We suggest that the horizontal motion of the granulation in the photosphere drives the magnetic reconnection, which is modulated by p-mode oscillations.

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Qiuzhuo Cai, Guiping Ruan, Chenxi Zheng, Brigitte Schmieder, Jinhan Guo, Yao Chen, Jiangtao Su, Yang Liu, Jihong Liu, Wenda Cao. 2023-12-07. Observational study of intermittent solar jets: p-mode modulation. https://arxiv.org/abs/2312.03571

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