ORIGIN OF CORONAL SHOCK WAVES ASSOCIATED WITH SLOW CORONAL MASS EJECTIONS

Journal Article · Tue Jul 20 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/718/1/266· OSTI ID:21455153

Magdalenic, J; Marque, C; Zhukov, A N ^[1]; Vrsnak, B; Zic, T ^[2]

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1. Solar Terrestrial Center of Excellence-SIDC, Royal Observatory of Belgium, Av. Circulaire 3, B-1180 Brussels (Belgium)
2. Hvar Observatory, Faculty of Geodesy, Kaciceva 26, HR-10000 Zagreb (Croatia)

We present a multiwavelength study of five coronal mass ejection/flare events (CME/flare) and associated coronal shock waves manifested as type II radio bursts. The study is focused on the events in which the flare energy release, and not the associated CME, is the most probable source of the shock wave. Therefore, we selected events associated with rather slow CMEs (reported mean velocity below 500 km s{sup -1}). To ensure minimal projection effects, only events related to flares situated close to the solar limb were included in the study. We used radio dynamic spectra, positions of radio sources observed by the Nancay Radioheliograph, GOES soft X-ray flux measurements, Large Angle Spectroscopic Coronagraph, and Extreme-ultraviolet Imaging Telescope observations. The kinematics of the shock wave signatures, type II radio bursts, were analyzed and compared with the flare evolution and the CME kinematics. We found that the velocities of the shock waves were significantly higher, up to one order of magnitude, than the contemporaneous CME velocities. On the other hand, shock waves were closely temporally associated with the flare energy release that was very impulsive in all events. This suggests that the impulsive increase of the pressure in the flare was the source of the shock wave. In four events the shock wave was most probably flare-generated, and in one event results were inconclusive due to a very close temporal synchronization of the CME, flare, and shock.

• OSTI ID: 21455153
• Journal Information: Astrophysical Journal, Vol. 718, Issue 1; Other Information: DOI: 10.1088/0004-637X/718/1/266; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
EXTREME ULTRAVIOLET RADIATION
MASS
SHOCK WAVES
SOFT X RADIATION
SOLAR CORONA
SOLAR FLARES
SOLAR SYSTEM EVOLUTION
SPECTRA
SUN
TELESCOPES
ATMOSPHERES
ELECTROMAGNETIC RADIATION
EVOLUTION
IONIZING RADIATIONS
MAIN SEQUENCE STARS
RADIATIONS
SOLAR ACTIVITY
SOLAR ATMOSPHERE
STARS
STELLAR ACTIVITY
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR FLARES
ULTRAVIOLET RADIATION
X RADIATION