A Statistical Study of the Average Iron Charge Distributions inside Magnetic Clouds for Solar Cycle 23

Abstract

Magnetic clouds (MCs) are the interplanetary counterpart of coronal magnetic flux ropes. They can provide valuable information to reveal the flux rope characteristics at their eruption stage in the corona, which are unable to be explored in situ at present. In this paper, we make a comprehensive survey of the average iron charge state (<Q>Fe) distributions inside 96 MCs for solar cycle 23 using ACE (Advanced Composition Explorer) data. As the <Q>Fe in the solar wind are typically around 9+ to 11+, the Fe charge state is defined as high when the <Q>Fe is larger than 12+, which implies the existence of a considerable amount of Fe ions with high charge states (e.g., \geq 16+). The statistical results show that the <Q>Fe distributions of 92 (~ 96%) MCs can be classified into four groups with different characteristics. In group A (11 MCs), the <Q>Fe shows a bimodal distribution with both peaks higher than 12+. Group B (4 MCs) presents a unimodal distribution of <Q>Fe with its peak higher than 12+. In groups C (29 MCs) and D (48 MCs), the <Q>Fe remains higher and lower than 12+ throughout ACE passage through the MC, respectively. Possible explanations to these distributions are discussed.

arXiv comment21 pages, 8 figures and 1 table. Accepted by the ApJ

References in corpus (14)

• A Model for Solar Coronal Mass Ejections
• Observation of An Evolving Magnetic Flux Rope Prior To and During A Solar Eruption
• Direct Evidence for a Fast CME Driven by the Prior Formation and Subsequent Destabilization of a Magnetic Flux Rope
• The Driver of Coronal Mass Ejections in the Low Corona: A Flux Rope
• Formation of a Double-decker Magnetic Flux Rope in the Sigmoidal Solar Active Region 11520
• Investigating plasma motion of magnetic clouds at 1 AU through a velocity-modified cylindrical force-free flux rope model
• Direct observations of magnetic flux rope formation during a solar coronal mass ejection
• Ion Charge States in Halo CMEs: What can we Learn about the Explosion?
• Temperature evolution of magnetic flux rope in a failed solar eruption
• Modeling UV and X-Ray Emission in a Post-CME Current Sheet
• Is flux rope a necessary condition for the progenitor of coronal mass ejections?
• Acceleration phases of a solar filament during its eruption
• Bright Ray-like Features in the Aftermath of CMEs: White Light vs UV Spectra
• First Taste of Hot Channel in Interplanetary Space

Cited by in corpus (9)

• The Origin of Solar Filament Plasma Inferred from in situ Observations of Elemental Abundances
• Characteristics and applications of interplanetary coronal mass ejection composition
• Solar Cycle Dependence of ICME Composition
• The high helium abundance and charge states of the interplanetary CME and its material source on the Sun
• Power-law Distribution of Solar-Cycle Modulated Coronal Jets
• Comparison of Helium Abundance between ICMEs and Solar Wind near 1 AU
• A statistical study of the plasma and composition distribution inside magnetic clouds: 1998-2011
• Composition Comparison between ICMEs from Active Regions and Quiet-Sun Regions
• The Inhomogeneity of Composition along the Magnetic Cloud Axis