2024/10/01 by Akshay Kumar Remeshan, Remeshan, Akshay Kumar, Mateja Dumbović +3 · 1 citation
Physics and Astronomy · #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Solar and Space Plasma Dynamics #Solar and Stellar Astrophysics (astro-ph.SR) #Space Physics (physics.space-ph)
paper · doi:10.48550/arxiv.2410.00615
openalex publication_date 2024/10/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We analyze the interaction between an Interplanetary Coronal Mass Ejection (ICME) detected in situ at the L1 Lagrange point on 2016 October 12 with a trailing High-Speed Stream (HSS). We aim to estimate the region in the interplanetary (IP) space where the interaction happened/started using a combined observational-modeling approach. We use Minimum Variance Analysis and the Walen test to analyze possible reconnection exhaust at the interface of ICME and HSS. We perform a Graduated Cylindrical Shell reconstruction of the CME to estimate the geometry and source location of the CME. Finally, we use a two-step Drag Based Model (DBM) model to estimate the region in IP space where the interaction took place. The magnetic obstacle (MO) observed in situ shows a fairly symmetric and undisturbed structure and shows the magnetic flux, helicity, and expansion profile/speed of a typical ICME. The MVA together with the Walen test, however, confirms reconnection exhaust at the ICME HSS boundary. Thus, in situ signatures are in favor of a scenario where the interaction is fairly recent. The trailing HSS shows a distinct velocity profile which first reaches a semi-saturated plateau with an average velocity of 500 km/s and then saturates at a maximum speed of 710 km/s . We find that the HSS interaction with the ICME is influenced only by this initial plateau. The results of the two-step DBM suggest that the ICME has started interacting with the HSS close to Earth (approx 0.81 au), which compares well with the deductions from in situ signatures.