DERIVING THE PHYSICAL PARAMETERS OF A SOLAR EJECTION WITH AN ISOTROPIC MAGNETOHYDRODYNAMIC EVOLUTIONARY MODEL

Journal Article · Tue Nov 01 00:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/741/1/47; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21612721

Berdichevsky, Daniel B ^[1]; Stenborg, Guillermo ^[2]; Vourlidas, Angelos ^[3]

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1. Department of Electrical and Computer Engineering, University of the District of Columbia, Washington, DC 20008 (United States)
2. College of Sciences, George Mason University, Fairfax, VA 22030 (United States)
3. Space Sciences Division, Naval Research Laboratory, Washington, DC 20375 (United States)

The time-space evolution of a {approx}50 Degree-Sign wide coronal mass ejection (CME) on 2007 May 21 is followed remotely with the Solar Terrestrial Relations Observatory heliospheric imager HI-1, and measured in situ near Venus by the MESSENGER and Venus-Express spacecraft. The paper compares the observations of the CME structure with a simple, analytical magnetohydrodynamic force-free solution. It corresponds to a self-similar evolution, which gives a consistent picture of the main spatial-temporal features for both remote and in situ observations. Our main findings are (1) the self-similar evolution allows us to map the CME bright front into about 1/3 of the whole interplanetary counterpart of the coronal mass ejection (ICME, i.e., corresponding to the in situ observed passage of the plasma and magnetic field structure), in good quantitative agreement with the imaging measurements, (2) the cavity following the CME front maps into the rest of the ICME structure, 80% or more of which is consistent with a force free, cylindrically shaped flux rope, and (3) time and space conditions constrain the translational speed of the FR center to 301 km s{sup -1}, and the expansion speed of the FR core to 26 km s{sup -1}. A careful determination of the ICME cross-section and volume allows us to calculate the mass of the CME bright region (4.3 {+-} 1.1 10{sup 14} g) from the in situ measurements of the proton number density, which we assume to be uniform inside the bright region, of excellent agreement with the value estimated from the SECCHI HI-1 observations for the same structure. We provide model estimates for several global parameters including FR helicity ({approx}2 Multiplication-Sign 10{sup 26} Weber{sup 2}).

• OSTI ID: 21612721
• Journal Information: Astrophysical Journal, Vol. 741, Issue 1; Other Information: DOI: 10.1088/0004-637X/741/1/47; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
CONVECTION
CROSS SECTIONS
DATA ANALYSIS
HELICITY
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MASS
MATHEMATICAL SOLUTIONS
SOLAR PROTONS
SOLAR SYSTEM EVOLUTION
SPACE-TIME
SUN
VELOCITY
VENUS PLANET
BARYONS
ELEMENTARY PARTICLES
ENERGY TRANSFER
EVOLUTION
FERMIONS
FLUID MECHANICS
HADRONS
HEAT TRANSFER
HYDRODYNAMICS
MAIN SEQUENCE STARS
MASS TRANSFER
MECHANICS
NUCLEONS
PARTICLE PROPERTIES
PLANETS
PROTONS
RADIATIONS
SOLAR PARTICLES
SOLAR RADIATION
STARS
STELLAR RADIATION