Source regions of the type II radio burst observed during a CME–CME interaction on 2013 May 22

0462222 - ÚFA 2017 RIV US eng J - Článek v odborném periodiku
Mäkelä, P. - Gopalswamy, N. - Reiner, M. J. - Akiyama, S. - Krupař, Vratislav
Source regions of the type II radio burst observed during a CME–CME interaction on 2013 May 22.
Astrophysical Journal. Roč. 827, č. 2 (2016), 141/1-141/7. ISSN 0004-637X. E-ISSN 1538-4357
Grant CEP: GA ČR(CZ) GAP209/12/2394
Grant ostatní: AV ČR(CZ) AP1401
Program: Akademická prémie - Praemium Academiae
Institucionální podpora: RVO:68378289
Klíčová slova: coronal mass ejections (CMEs) * radio radiation
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
Impakt faktor: 5.533, rok: 2016
http://iopscience.iop.org/article/10.3847/0004-637X/827/2/141

We report on our study of radio source regions during the type II radio burst on 2013 May 22 based on direction-finding analysis of the Wind/WAVES and STEREO/WAVES (SWAVES) radio observations at decameter–hectometric wavelengths. The type II emission showed an enhancement that coincided with the interaction of two coronal mass ejections (CMEs) launched in sequence along closely spaced trajectories. The triangulation of the SWAVES source directions posited the ecliptic projections of the radio sources near the line connecting the Sun and the STEREO-A spacecraft. The WAVES and SWAVES source directions revealed shifts in the latitude of the radio source, indicating that the spatial location of the dominant source of the type II emission varies during the CME–CME interaction. The WAVES source directions close to 1 MHz frequencies matched the location of the leading edge of the primary CME seen in the images of the LASCO/C3 coronagraph. This correspondence of spatial locations at both wavelengths confirms that the CME–CME interaction region is the source of the type II enhancement. Comparison of radio and white-light observations also showed that at lower frequencies scattering significantly affects radio wave propagation.
Trvalý link: http://hdl.handle.net/11104/0261711