Abstract Using high-resolution photospheric and chromospheric observations taken by the Goode Solar Telescope, we studied two groups of bidirectional plasma jets occurring in active region NOAA 13110. Supplementary observations are also provided by Solar Dynamics Observatory’s Atmospheric Imaging Assembly and Helioseismic and Magnetic Imager. From the photospheric observations and magnetograms, the two successive bidirectional plasma jets were initially located in the vicinity of the polarity inversion lines and at the intersection of the umbra and penumbra of the sunspot, followed by magnetic flux emergence and cancellation. As the cool filamentary threads are continuously emerging from the lower chromosphere and interact with overlying horizontal magnetic loops, it leads to the bidirectional jets, erupting outflow plasmoids, and heating coronal magnetic loops. We find that the bidirectional jets extended from the central excitation location in opposite directions, at the speed of about dozens of km s −1 . For the first jet, the initial brightening first appears in 304 Å, about 30 s earlier than the H α observations, indicating that magnetic reconnection takes place in the transition region. Meanwhile, the initial reconnection for the second jet occurs simultaneously in H α and 304 Å, showing the recurrent eruptions. These observations confirm that the bidirectional plasma jets can be generated by magnetic reconnection between the rising filamentary threads or material and the overlying horizontal magnetic loops. Our results provide new insights into the generation of the bidirectional plasma jets and reconnection-based coronal heating.
Liu et al. (2026) studied this question.