In Situ Observation of Alfvén Waves in an ICME Shock-Sheath Indicating the Existence of Alfvénic Turbulence

Dhamane, Omkar; Raghav, Anil; Shaikh, Zubair; Pawaskar, Vinit; Ghag, Kalpesh; Tari, Prathmesh; Panchal, Utsav

doi:10.1007/s11207-024-02271-5

Cited by 1 publication

(2 citation statements)

References 135 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The magnetic and kinetic forces within ICMEs are no longer in perfect equilibrium, leading to the excitation of both MHD and kinetic-scale waves (Jacques 1977). While previous studies have delved into MHD-scale waves within magnetic clouds (Raghav & Kule 2018a, 2018bRaghav et al 2018Raghav et al , 2019Raghav et al , 2023aDhamane et al 2023bDhamane et al , 2024, the understanding of kinetic-scale mode waves remains a challenge. In a recent study, Dhamane et al (2023a) observed one aspect of kineticscale waves, specifically those aligned with the background magnetic field, by studying Alfvén ion cyclotron waves.…”

Section: Resultsmentioning

confidence: 99%

“…The interactions between ICMEs and between an ICME and highspeed streams generate Alfvén waves, and their propagation in an ICME may disrupt its ordered flux rope structure (Raghav & Kule 2018a, 2018bDhamane et al 2023b). Very recently, Alfvén waves and Alfvén ion cyclotron waves have been identified in ICME-driven sheath regions (Raghav & Shaikh 2018;Ala-Lahti et al 2019;Shaikh et al 2019;Dhamane et al 2024). Moreover, Li et al (2017) suggested that dissipation of Alfvénic fluctuations is responsible for local plasma heating inside the ICMEs.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Observation of Kinetic Alfvén Waves inside an Interplanetary Coronal Mass Ejection Magnetic Cloud at 1 au

Kumbhar,

Raghav,

Dhamane

et al. 2024

ApJ

Self Cite

View full text Add to dashboard Cite

Recent advancements have significantly enhanced our grasp of interplanetary coronal mass ejections (ICMEs) in the heliosphere. These observations have uncovered complex kinematics and structural deformations in ICMEs, hinting at the possible generation of magnetohydrodynamic (MHD) and kinetic-scale waves. While MHD-scale waves in magnetic clouds have been explored, understanding the dynamics of kinetic-scale mode waves remains challenging. This article demonstrates the first in situ observation of kinetic Alfvén waves (KAWs) within an ICME’s magnetic cloud, notably near the heliospheric current sheet–ICME interaction region, close to the reconnection exhaust. Analysis indicates a distinctive negative bump in the estimated normalized magnetic helicity (σ m = −0.38) around the gyrofrequency spread, indicating a right-handed polarization of the wave. Furthermore, examination across flow angle (θ VB) within the frequency domain reveals a specific zone (90°–135°) showcasing negative helicity fluctuations, confirming the presence of KAWs. Moreover, we noted a significant rise in temperature anisotropy in the vicinity, indicating the role of KAWs in plasma heating. Identifying KAW challenges established notions about ordered magnetic clouds and raises questions about energy transfer processes within these structures. This finding opens the door to a deeper understanding of energy transfer mechanisms within traditionally nondissipative regions and invites further exploration of low-beta plasma heating and the interactions between waves and particles in magnetic clouds.

show abstract