Torsional Alfven wave embedded ICME magnetic cloud and corresponding geomagnetic storm

Abstract

The energy transfer during the interaction of large-scale solar wind structure and the Earth's magnetosphere is the chronic issue in space-weather studies. To understand this, researchers widely studied the geomagnetic storms and sub-storms phenomena. The present understanding suggests that long duration of southward interplanetary magnetic field component is the most important parameter for the geomagnetic storm. Such long duration strong southward magnetic field is often associated with ICMEs, torsional Alfven fluctuations superposed co-rotating interacting regions (CIRs) and fast solar wind streams. Torsional Alfven fluctuations embedded CIRs have been known for a long, however magnetic cloud embedded with such fluctuations are rarely observed. The presence of Alfven waves in the ICME/MC and influence of these waves on the storm evolution remains an interesting topic of study. The present work confirms the torsional Alfven waves in a magnetic cloud associated with a CME launched on 15th February which impacted the Earth's magnetosphere on February 18, 2011. Further, observations indicate that these waves inject energy into the magnetosphere during the storm and contribute to the long recovery time of geomagnetic storms. Our study suggests that presence of torsional Alfven waves significantly controls the storm dynamics.

References in corpus (8)

• The Emergence of a Twisted Flux Tube into the Solar Atmosphere: Sunspot Rotations and the Formation of a Coronal Flux Rope
• Signatures of Alfven waves in the polar coronal holes as seen by EIS/Hinode
• Asymmetry in the CME-CME interaction process for the events from 2011 February 14-15
• Signatures of magnetic reconnection at boundaries of interplanetary small-scale magnetic flux ropes
• Morphological and Kinematic Evolution of Three Interacting Coronal Mass Ejections of 2011 February 13-15
• Understanding Forbush decrease drivers based on shock-only and CME-only models using global signature of February 14, 1978 event
• Does Local Structure Within Shock-sheath and Magnetic Cloud Affect Cosmic Ray Decrease?
• The first in-situ observation of torsional Alfven waves during the interaction of large-scale magnetic clouds

Cited by in corpus (5)

• Temporal Variations of the Three Geomagnetic Field Components at Colaba Observatory around the Carrington Storm in 1859
• Torsional Alfvénic Oscillations Discovered in the Magnetic Free Energy During Solar Flares
• Observation of Alfven wave in ICME-HSS interaction region
• First analysis of in-situ observation of surface Alfvén waves in ICME flux rope
• Chirality and magnetic configuration associated with two-ribbon solar flares: AR 10930 versus AR 11158