THE ENERGETICS OF A GLOBAL SHOCK WAVE IN THE LOW SOLAR CORONA

Journal Article · Sun Feb 01 04:00:00 EST 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/799/2/224· OSTI ID:22364309

Long, David M.; Baker, Deborah; Williams, David R. ^[1]; Carley, Eoin P.; Gallagher, Peter T.; Zucca, Pietro ^[2]

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1. Mullard Space Science Laboratory (UCL), Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)
2. Astrophysics Research Group, School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

As the most energetic eruptions in the solar system, coronal mass ejections (CMEs) can produce shock waves at both their front and flanks as they erupt from the Sun into the heliosphere. However, the amount of energy produced in these eruptions, and the proportion of their energy required to produce the waves, is not well characterized. Here we use observations of a solar eruption from 2014 February 25 to estimate the energy budget of an erupting CME and the globally propagating ''EIT wave'' produced by the rapid expansion of the CME flanks in the low solar corona. The ''EIT wave'' is shown using a combination of radio spectra and extreme ultraviolet images to be a shock front with a Mach number greater than one. Its initial energy is then calculated using the Sedov-Taylor blast-wave approximation, which provides an approximation for a shock front propagating through a region of variable density. This approach provides an initial energy estimate of ≈2.8 × 10{sup 31} erg to produce the ''EIT wave'', which is approximately 10% the kinetic energy of the associated CME (shown to be ≈2.5 × 10{sup 32} erg). These results indicate that the energy of the ''EIT wave'' may be significant and must be considered when estimating the total energy budget of solar eruptions.

• OSTI ID: 22364309
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 799; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
APPROXIMATIONS
DENSITY
EXTREME ULTRAVIOLET RADIATION
HELIOSPHERE
KINETIC ENERGY
MACH NUMBER
MASS
SHOCK WAVES
SOLAR CORONA
SOLAR SYSTEM
SUN
WAVE PROPAGATION