Triple-point magnetic flux rope analysis for the 2020 April 19 CME observed in situ by Solar Orbiter, Bepi Colombo, and WIND

<p>We present initial results for a triple-point analysis for the in situ magnetic field measurements of a CME observed at three independent locations. On the 19th of April 2020, Solar Orbiter observed a CME in situ at a radial distance of around&#160;0.8 au. This CME was subsequently also detected by the Wind and Bepi Colombo satellites closer to Earth. This triple in situ measurement of a CME provides us the unique opportunity to test the consistency of the measurements with our own 3D Coronal Rope Ejection (3DCORE) model. A triple measurement allows for up to seven different data combinations to be analyzed (three single-point, three dual-point, and one single triple-point combination) which gives us&#160;information on how our analysis pipeline responds to multi-point measurements and how the results change with measurements at differing radial and longitudinal distances. The goal of this study is to test whether all three in situ measurements can still be described by a slightly bent flux rope geometry and how adding additional&#160;measurements can improve the accuracy of inferred model parameters.</p>

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Examining the magnetic geometry of magnetic flux rope: from the view of single-point analysis

10.1002/essoar.10502861.1 ◽

2020 ◽

Author(s):

Zhaojin Rong ◽

Chi Zhang ◽

Chao Shen ◽

Lucy Klinger ◽

Jiawei Gao ◽

...

Keyword(s):

Magnetic Flux ◽

Single Point ◽

Flux Rope ◽

Magnetic Flux Rope ◽

Point Analysis

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In Situ Models, Physico-Chemical Aspects

Advances in Dental Research ◽

10.1177/08959374940080020201 ◽

1994 ◽

Vol 8 (2) ◽

pp. 125-133 ◽

Cited By ~ 27

Author(s):

J.M. Ten Cate

Keyword(s):

Single Point ◽

Limiting Factor ◽

Model Parameters ◽

Laboratory Findings ◽

Physiological Processes ◽

Physico Chemical ◽

Crystallite Surface ◽

Mineral Loss

In situ (intra-oral) caries models are used for two purposes. First, they provide information about oral physiological processes. Such information helps to detail our knowledge of the oral ecosystem and to verify conclusions from in vitro experiments. Second, in situ models are utilized to test preventive agents in the phase between laboratory testing and clinical trials. Most investigations involving enamel inserts have been aimed at testing new dentifrices. The experimental designs of such studies usually do not allow one to draw conclusions on physico-chemical processes, e.g., because of single point measurements. Studies of model parameters (lesion type, lesion severity, and de/remineralization in time) constitute only a minority of the research reports. The most striking observation obtained with in situ models has been the significant differences in de/remineralization observed among individuals and, more importantly, within one individual during different time periods and between different sites in the same mouth (for review, see ten Cate et al., 1992). Regardless of this, some general findings can be inferred: During in situ demineralization, up to 62 vol%μm/day may be removed from enamel. For dentin specimens, this value may be as high as 89 vol%μm/day. For remineralization, during fluoride dentifrice treatment, a median deposition rate of 0.7%/day (for lesions with integrated mineral loss values between 2000 and 4000 vol%μm) is found. The rate of deposition seems to be correlated with the extent of the pre-formedlesion. This suggests that the number of sites (crystallite surface) available for calcium phosphate precipitation is an important parameter. However, the rate at which mineral ions are supplied (by saliva) could also be a limiting factor, as is shown in a theoretical analysis of mass-balance of enamel constituents. The few studies that have monitored caries development in time reveal that mineral loss (and also lesion progression in depth) from enamel in situ is linear in time. This is in contrast to results from laboratory findings.

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The in-situ manifestation of solar prominence material

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313011113 ◽

2013 ◽

Vol 8 (S300) ◽

pp. 289-296 ◽

Cited By ~ 1

Author(s):

Susan T. Lepri ◽

Thomas H. Zurbuchen ◽

Jacob R. Gruesbeck ◽

Jason A. Gilbert

Keyword(s):

Solar Wind ◽

Flux Rope ◽

Ion Composition ◽

Solar Prominence ◽

Magnetic Flux Rope ◽

Analysis Process ◽

Part Structure ◽

Low Charge

AbstractCoronal mass ejections observed in the corona exhibit a three-part structure, with a leading bright front indicating dense plasma, a low density cavity thought to be a signature of the embedded magnetic flux rope, and the high density core likely containing cold, prominence material. When observed in-situ, as Interplanetary CMEs (or ICMEs), the presence of all three of these signatures remains elusive, with the prominence material rarely observed. We report on a comprehensive and long-term search for prominence material inside ICMEs as observed by the Solar Wind Ion Composition Spectrometer on the Advanced Composition Explorer. Using a novel data analysis process, we are able to identify traces of low charge state plasma created during prominence eruptions associated with ICMEs. We find that the likelihood of occurrence of cold material in the heliosphere is vastly lower than that observed in the corona but that conditions during the eruption do allow low charge ions to make it into the solar wind, preserving their expansion history. We discuss the implications of these findings.

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Complex Evolution of Coronal Mass Ejections in the Inner Heliosphere as Revealed by Numerical Simulations and STEREO Observations: A Review

Proceedings of the International Astronomical Union ◽

10.1017/s174392131301106x ◽

2013 ◽

Vol 8 (S300) ◽

pp. 255-264 ◽

Cited By ~ 1

Author(s):

Noé Lugaz ◽

Charles J. Farrugia ◽

Nada Al-Haddad

Keyword(s):

Numerical Simulations ◽

Coronal Mass Ejections ◽

Flux Rope ◽

Magnetic Flux Rope ◽

Work Related ◽

The Core ◽

The Past ◽

Complex Models ◽

Inner Heliosphere

AbstractThe transit of coronal mass ejections (CMEs) from the Sun to 1 AU lasts on average one to five days. As they propagate, CMEs interact with the solar wind and preceding eruptions, which modify their properties. In the past ten years, the evolution of CMEs in the inner heliosphere has been investigated with the help of numerical simulations, through the analysis of remote-sensing heliospheric observations, especially with the SECCHI suite onboard STEREO, and through the analysis of multi-spacecraft in situ measurements. Most studies have focused on understanding the characteristics of the magnetic flux rope thought to form the core of the CME. Here, we first review recent work related to CME propagation in the heliosphere, which point towards the need to develop more complex models to analyze CME observations. In the second part of this article, we review some recent studies of CME-CME interaction, which also illustrate the complexity of phenomena occurring in the inner heliosphere.

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3-D views of the expanding CME: from the Sun to 1AU

Proceedings of the International Astronomical Union ◽

10.1017/s174392131400475x ◽

2012 ◽

Vol 10 (H16) ◽

pp. 106-108

Author(s):

Alexis P. Rouillard

Keyword(s):

Extreme Ultraviolet ◽

Three Dimensional ◽

Flux Rope ◽

In Situ Measurements ◽

Magnetic Flux Rope ◽

Wide Range ◽

Remote Sensing Techniques ◽

Vantage Points ◽

White Light Imaging

AbstractThree-dimensional information on Coronal Mass Ejections (CMEs) can be obtained from a wide range of in-situ measurements and remote-sensing techniques. Extreme ultraviolet (EUV) and white-light imaging sensed from several vantage points can be used to infer the 3-D geometry of the different parts that constitute a CME. High-resolution and high-cadence coronal imaging provides detailed information on the formation and release phase of a magnetic flux rope, the lateral expansion of the CME and the reconfiguration of the corona associated with the effects of pressure variations and reconnection. The evolution of the CME in the interplanetary medium and the connection of its various substructures with in-situ measurements can be obtained from multi-point heliospheric imaging.

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Method for inferring the axis orientation of cylindrical magnetic flux rope based on single-point measurement

Journal of Geophysical Research Space Physics ◽

10.1029/2012ja018079 ◽

2013 ◽

Vol 118 (1) ◽

pp. 271-283 ◽

Cited By ~ 14

Author(s):

Z. J. Rong ◽

W. X. Wan ◽

C. Shen ◽

T. L. Zhang ◽

A. T. Y. Lui ◽

...

Keyword(s):

Magnetic Flux ◽

Single Point ◽

Flux Rope ◽

Axis Orientation ◽

Magnetic Flux Rope ◽

Point Measurement

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Reconstruction of magnetic clouds from in-situ spacecraft measurements and intercomparison with their solar sources

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313011083 ◽

2013 ◽

Vol 8 (S300) ◽

pp. 269-272

Author(s):

Qiang Hu ◽

Jiong Qiu

Keyword(s):

Magnetic Flux ◽

Field Line ◽

Source Region ◽

Flux Rope ◽

Magnetic Clouds ◽

Reconstruction Technique ◽

Magnetic Flux Rope ◽

Solar Material ◽

Physical Quantities

AbstractCoronal Mass Ejections (CMEs) are eruptive events that originate, propagate away from the Sun, and carry along solar material with embedded solar magnetic field. Some are accompanied by prominence eruptions. A subset of the interplanetary counterparts of CMEs (ICMEs), so-called Magnetic Clouds (MCs) can be characterized by magnetic flux-rope structures. We apply the Grad-Shafranov (GS) reconstruction technique to examine the configuration of MCs and to derive relevant physical quantities, such as magnetic flux content, relative magnetic helicity, and the field-line twist, etc. Both observational analyses of solar source region characteristics including flaring and associated magnetic reconnection process, and the corresponding MC structures were carried out. We summarize the main properties of selected events with and without associated prominence eruptions. In particular, we show the field-line twist distribution and the intercomparison of magnetic flux for these flux-rope structures.

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Small-scale Magnetic Flux Ropes with Field-aligned Flows via the PSP In-situ Observations

10.5194/egusphere-egu21-8043 ◽

2021 ◽

Author(s):

Yu Chen ◽

Qiang Hu ◽

Lingling Zhao

Keyword(s):

Magnetic Field ◽

Magnetic Flux ◽

Flux Rope ◽

Local Magnetic Field ◽

Small Scale ◽

Magnetic Flux Rope ◽

Magnetic Flux Ropes ◽

Flux Ropes ◽

Field Lines

<p>Magnetic flux rope, formed by the helical magnetic field lines, can sometimes remain its shape while carrying significant plasma flow that is aligned with the local magnetic field. We report the existence of such structures and static flux ropes by applying the Grad-Shafranov-based algorithm to the Parker Solar Probe (PSP) in-situ measurements in the first five encounters. These structures are detected at heliocentric distances, ranging from 0.13 to 0.66 au, in a total of 4-month time period. We find that flux ropes with field-aligned flows have certain properties similar to those of static flux ropes, such as the decaying relations of the magnetic fields within structures with respect to heliocentric distances. Moreover, these events are more likely with magnetic pressure dominating over the thermal pressure and occurring more frequently in the relatively fast-speed solar wind. Taking into account the high Alfvenicity, we also compare these events with switchbacks and present the cross-section maps via the new Grad-Shafranov type reconstruction. Finally, the possible evolution and relaxation of the magnetic flux rope structures are discussed.</p>

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