Quantifying the Propagation of Fast Coronal Mass Ejections from the Sun to Interplanetary Space by Combining Remote Sensing and Multi-point In Situ Observations

Abstract. We analyze two magnetic clouds (MCs) observed in different points of the heliosphere. The main aim of the present study is to provide a link between the different aspects of this phenomenon, starting with information on the origins of the MCs at the Sun and following by the analysis of in-situ observations at 1 AU and at Ulysses. The candidate source regions were identified in SOHO/EIT and SOHO/MDI observations. They were correlated with H-α images that were obtained from ground-based observatories. Hints on the internal magnetic field configuration of the associated coronal mass ejections are obtained from LASCO C2 images. In interplanetary space, magnetic and plasma moments of the distribution function of plasma species (ACE/Ulysses) were analyzed together with information on the plasma composition, and the results were compared between both spacecraft in order to understand how these structures interact and evolve in their cruise from the Sun to 5 AU. Additionally, estimates of global magnitudes of magnetic fluxes and helicity were obtained from magnetic field models applied to the data in interplanetary space. We have found that these magnetic characteristics were well kept from their solar source, up to 5 AU where Ulysses provided valuable information which, together with that obtained from ACE, can help to reinforce the correct matching of solar events and their interplanetary counterparts.

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Observing the Sun with LOFAR: an overview of the telescope capabilities and the recent results from the PSP groud base support campaign.

10.5194/egusphere-egu21-15048 ◽

2021 ◽

Author(s):

Pietro Zucca

Keyword(s):

Remote Sensing ◽

Solar Wind ◽

Interplanetary Space ◽

Ground Truth ◽

Flow Speed ◽

Radio Sources ◽

Turbulence Structure ◽

The Sun ◽

Plasma Parameters

<p>Understanding and modelling the complex state of the Sun-solar wind-heliosphere&#160;system, requires a comprehensive set of multiwavelength observations. LOFAR&#160;has unique capabilities in the radio domain. Some examples of these include: a) the ability&#160;to take high-resolution solar dynamic spectra and radio images of the Sun; b) observing the&#160;scintillation (interplanetary scintillation - IPS) of distant, compact, astronomical radio sources&#160;to determine the density, velocity and turbulence structure of the solar wind; and c) the use of&#160;Faraday rotation as a tool to probe the interplanetary magnetic-field strength and direction.&#160;However, to better understand and predict how the Sun, its atmosphere, and more in general&#160;the Heliosphere works and impacts Earth, the combination of in-situ spacecraft measurements&#160;and ground-based remote-sensing observations of coronal and heliospheric plasma parameters is&#160;extremely useful. Ground-based observations can be used to infer a global picture of the inner&#160;heliosphere, providing the essential context into which in-situ measurements from spacecraft can&#160;be placed. Conversely, remote-sensing observations usually contain information from extended&#160;lines of sight, with some deconvolution and modelling necessary to build up a three-dimensional&#160;(3-D) picture. Precise spacecraft measurements, when calibrated, can provide ground truth to&#160;constrain these models. The PSP mission is observing the solar corona and near-Sun interplanetary&#160;space. It has a highly-elliptical orbit taking the spacecraft as close as nearly 36 sola&#160;radii from the Sun centre on its first perihelion passage, and subsequent passages ultimately&#160;reaching as close as 9.8 solar radii. Four instruments are on the spacecraft&#8217;s payload: FIELDS&#160;measuring the radio emission, electric and magnetic fields, Poynting flux, and plasma waves&#160;as well as the electron density and temperature; ISOIS measuring energetic electrons, protons,&#160;and heavy ions in the energy range 10 keV-100 MeV; SWEAP measuring the density, temperature,&#160;and flow speed of electrons, protons, and alphas in the solar wind; and finally, WISPR&#160;imaging coronal streamers, coronal mass ejections (CMEs), their associated shocks, and other&#160;solar wind structures in the corona and near-Sun interplanetary space, and provide context for&#160;the other three in-situ instruments. In this talk, the different observing modes of LOFAR and&#160;several results of the joint LOFAR/PSP campaign&#160;will be presented, including fine structures of radio bursts, localization and kinematics of&#160;propagating radio sources in the heliosphere, and the challenges and plans for future observing&#160;campaigns including PSP and Solar Orbiter.</p><p>&#160;</p>

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Solar Filaments as Tracers of Subsurface Processes

International Astronomical Union Colloquium ◽

10.1017/s0252921100064459 ◽

2000 ◽

Vol 179 ◽

pp. 177-183

Author(s):

D. M. Rust

Keyword(s):

Magnetic Fields ◽

Magnetic Flux ◽

Coronal Mass Ejections ◽

Interplanetary Space ◽

Intermediate Stage ◽

Coronal Plasma ◽

Magnetic Helicity ◽

The Sun ◽

New Paradigm ◽

Solar Filaments

AbstractSolar filaments are discussed in terms of two contrasting paradigms. The standard paradigm is that filaments are formed by condensation of coronal plasma into magnetic fields that are twisted or dimpled as a consequence of motions of the fields’ sources in the photosphere. According to a new paradigm, filaments form in rising, twisted flux ropes and are a necessary intermediate stage in the transfer to interplanetary space of dynamo-generated magnetic flux. It is argued that the accumulation of magnetic helicity in filaments and their coronal surroundings leads to filament eruptions and coronal mass ejections. These ejections relieve the Sun of the flux generated by the dynamo and make way for the flux of the next cycle.

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Transforming in-situ observations of CME-driven shock accelerated protons into the shock's reference frame.

Annales Geophysicae ◽

10.5194/angeo-23-1931-2005 ◽

2005 ◽

Vol 23 (5) ◽

pp. 1931-1941 ◽

Cited By ~ 1

Author(s):

I. M. Robinson ◽

G. M. Simnett

Keyword(s):

Solar Physics ◽

Solar Energetic Particle ◽

Transport Processes ◽

Solar Energetic Particle Event ◽

The Sun ◽

Proton Acceleration ◽

Angle Scattering ◽

Peak Energy ◽

In Situ Observations

Abstract. We examine the solar energetic particle event following solar activity from 14, 15 April 2001 which includes a "bump-on-the-tail" in the proton energy spectra at 0.99 AU from the Sun. We find this population was generated by a CME-driven shock which arrived at 0.99 AU around midnight 18 April. As such this population represents an excellent opportunity to study in isolation, the effects of proton acceleration by the shock. The peak energy of the bump-on-the-tail evolves to progressively lower energies as the shock approaches the observing spacecraft at the inner Lagrange point. Focusing on the evolution of this peak energy we demonstrate a technique which transforms these in-situ spectral observations into a frame of reference co-moving with the shock whilst making allowance for the effects of pitch angle scattering and focusing. The results of this transform suggest the bump-on-the-tail population was not driven by the 15 April activity but was generated or at least modulated by a CME-driven shock which left the Sun on 14 April. The existence of a bump-on-the-tail population is predicted by models in Rice et al. (2003) and Li et al. (2003) which we compare with observations and the results of our analysis in the context of both the 14 April and 15 April CMEs. We find an origin of the bump-on-the-tail at the 14 April CME-driven shock provides better agreement with these modelled predictions although some discrepancy exists as to the shock's ability to accelerate 100 MeV protons. Keywords. Solar physics, astrophysics and astronomy (Energetic particles; Flares and mass ejections) – Space plasma physics (Transport processes)

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Estudo do ciclo diário da Camada Limite Planetária durante a estação cChuvosa da Amazônia (GOAmazon 2014/15)

Ciência e Natura ◽

10.5902/2179460x30650 ◽

2018 ◽

Vol 40 ◽

pp. 63 ◽

Cited By ~ 1

Author(s):

Rayonil Gomes Carneiro ◽

Alice Henkes ◽

Gilberto Fisch ◽

Camilla Kassar Borges

Keyword(s):

Remote Sensing ◽

Boundary Layer ◽

Planetary Boundary Layer ◽

Remote Sensing Data ◽

Great Depth ◽

Wet Season ◽

Daily Cycle ◽

Convective Boundary ◽

In Situ Observations

In the present study, the evolution the diurnal cycle of planetary boundary layer in the wet season at Amazon region during a period of intense observations carried out in the GOAmazon Project 2014/2015 (Green Ocean Amazon).The analysis includes radiosonde and remote sensing data. In general case, the results of the daily cycle in the wet season indicate a Nocturnal boundary layer with a small oscillation in its depth and with a tardy erosion. The convective boundary layer did not present great depth, responding to the low values of sensible heat of the wet season. A comparison between the different techniques(in situ observations and remote sensing) for estimating the planetary boundary layer is also presented.

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Characterization of Remote Sensing Albedo Over Sloped Surfaces Based on DART Simulations and In Situ Observations

Journal of Geophysical Research Atmospheres ◽

10.1029/2018jd028283 ◽

2018 ◽

Vol 123 (16) ◽

pp. 8599-8622 ◽

Cited By ~ 5

Author(s):

Shengbiao Wu ◽

Jianguang Wen ◽

Dongqin You ◽

Dalei Hao ◽

Xingwen Lin ◽

...

Keyword(s):

Remote Sensing ◽

In Situ Observations

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Three-phase Evolution of a Coronal Hole. I. 360° Remote Sensing and In Situ Observations

The Astrophysical Journal ◽

10.3847/1538-4357/aac897 ◽

2018 ◽

Vol 861 (2) ◽

pp. 151 ◽

Cited By ~ 16

Author(s):

Stephan G. Heinemann ◽

Manuela Temmer ◽

Stefan J. Hofmeister ◽

Astrid M. Veronig ◽

Susanne Vennerstrøm

Keyword(s):

Remote Sensing ◽

Coronal Hole ◽

Phase Evolution ◽

Three Phase ◽

In Situ Observations

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The role of aerodynamic drag in dynamics of coronal mass ejections

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309029391 ◽

2008 ◽

Vol 4 (S257) ◽

pp. 271-277

Author(s):

Bojan Vršnak ◽

Dijana Vrbanec ◽

Jaša Čalogović ◽

Tomislav Žic

Keyword(s):

Solar Wind ◽

Wind Speed ◽

Coronal Mass Ejections ◽

Weather Forecasting ◽

Aerodynamic Drag ◽

Interplanetary Space ◽

Solar Wind Speed ◽

Standard Form ◽

The Sun

AbstractDynamics of coronal mass ejections (CMEs) is strongly affected by the interaction of the erupting structure with the ambient magnetoplasma: eruptions that are faster than solar wind transfer the momentum and energy to the wind and generally decelerate, whereas slower ones gain the momentum and accelerate. Such a behavior can be expressed in terms of “aerodynamic” drag. We employ a large sample of CMEs to analyze the relationship between kinematics of CMEs and drag-related parameters, such as ambient solar wind speed and the CME mass. Employing coronagraphic observations it is demonstrated that massive CMEs are less affected by the aerodynamic drag than light ones. On the other hand, in situ measurements are used to inspect the role of the solar wind speed and it is shown that the Sun-Earth transit time is more closely related to the wind speed than to take-off speed of CMEs. These findings are interpreted by analyzing solutions of a simple equation of motion based on the standard form for the drag acceleration. The results show that most of the acceleration/deceleration of CMEs on their way through the interplanetary space takes place close to the Sun, where the ambient plasma density is still high. Implications for the space weather forecasting of CME arrival-times are discussed.

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