Investigation of an X-class Flare and Quasi-Periodic Pulsations in NOAA AR 13842 using SDO, Aditya-L1 and Solar Orbiter

@misc{kumara2026investigation,
  title = {{Investigation of an X-class Flare and Quasi-Periodic Pulsations in NOAA AR 13842 using SDO, Aditya-L1 and Solar Orbiter}},
  author = {Pawan Kumara and Sanjay Kumara and Sushree S. Nayak and Sadashiv and Sachin Rajkapoor Kanaujiyac and Ramesh Chandrad},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.22165},
  eprint = {2610.22165},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.22165},
}

TY  - UNPB
TI  - Investigation of an X-class Flare and Quasi-Periodic Pulsations in NOAA AR 13842 using SDO, Aditya-L1 and Solar Orbiter
AU  - Pawan Kumara
AU  - Sanjay Kumara
AU  - Sushree S. Nayak
AU  - Sadashiv
AU  - Sachin Rajkapoor Kanaujiyac
AU  - Ramesh Chandrad
PY  - 2026
DA  - 2026/10/15
PB  - arXiv
DO  - 10.48550/arxiv.2610.22165
UR  - https://arxiv.org/abs/2610.22165
AB  - We investigate an X9.0 class flare (SOL2024-10-03T12:08) and associated quasi-periodic pulsations (QPPs) in NOAA active region (AR) 13842 using observations from the Solar Dynamics Observatory (SDO), Aditya-L1 and Solar Orbiter (SO). To explore the role of magnetic configuration in the flare, we employ non-force-free-field extrapolation technique for reconstructing a sequence of the coronal magnetic field throughout the flare. The observations reveal the emergence of intricate flare brightenings and ribbons. QPPs are observed with periods of ≈ 2 and ≈ 6 minutes in EUV, ≈ 7 minutes in UV, and ≈ 1 minute in X-rays. The extrapolation documents the presence of a flux rope, a sheared arcade, and a hyperbolic flux tube (HFT) enveloping the rope and the arcade. The sequence of the extrapolation illustrates an increase in the twist of the rope as it ascends towards a torus-unstable region, thereby rendering the rope a viable candidate for eruption. The sheared arcade appears to generate electric current through its foot-point's motion, which explains the sigmoidal brightening observed at the flare onset. The motion also seems to drive the non-parallel field lines closer together, heightening gradient in the magnetic field beneath the rope. Consequently, recurrent magnetic reconnection is anticipated within the sheared arcade --- explaining the ascent of the rope with its twist increment. The formation of parallel flare ribbons is attributed to these reconnections. Furthermore, reconnection at the HFT is proposed to lead the remote and quasi-circular ribbons. Crucially, repeated reconnections inside the arcade as well as at the HFT are speculated to cause the QPPs.
ER  -