Ref: SCART-2019-0133

Tracking of an electron beam through the solar corona with LOFAR

Mann, G. ; Breitling, F. ; Vocks, C. ; Aurass, H. ; Steinmetz, M. ; Strassmeier, K. G. ; Bisi, M. M. ; Fallows, R. A. ; Gallagher, P. ; Kerdraon, A. ; Mackinnon, A. ; Magdalenic, J. ; Rucker, H. ; Anderson, J. ; Asgekar, A. ; Avruch, I. M. ; Bell, M. E. ; Bentum, M. J. ; Bernardi, G. ; Best, P. ; Birzan, L. ; Bonafede, A. ; Broderick, J. W. ; Bruggen, M. ; Butcher, H. R. ; Ciardi, B. ; Corstanje, A. ; Gasperin, F. de ; Geus, E. de ; Deller, A. ; Duscha, S. ; Eisloffel, J. ; Engels, D. ; Falcke, H. ; Fender, R. ; Ferrari, C. ; Frieswijk, W. ; Garrett, M. A. ; Grießmeier, J. ; Gunst, A. W. ; van Haarlem, M. ; Hassall, T. E. ; Heald, G. ; Hessels, J. W. T. ; Hoeft, M. ; Horandel, J. ; Horneffer, A. ; Juette, E. ; Karastergiou, A. ; Klijn, W. F. A. ; Kondratiev, V. I. ; Kramer, M. ; Kuniyoshi, M. ; Kuper, G. ; Maat, P. ; Markoff, S. ; McFadden, R. ; McKay-Bukowski, D. ; McKean, J. P. ; Mulcahy, D. D. ; Munk, H. ; Nelles, A. ; Norden, M. J. ; Orru, E. ; Paas, H. ; Pandey-Pommier, M. ; Pandey, V. N. ; Pizzo, R. ; Polatidis, A. G. ; Rafferty, D. ; Reich, W. ; Rottgering, H. ; Scaife, A. M. M. ; Schwarz, D. J. ; Serylak, M. ; Sluman, J. ; Smirnov, O. ; Stappers, B. W. ; Tagger, M. ; Tang, Y. ; Tasse, C. ; ter Veen, S. ; Thoudam, S. ; Toribio, M. C. ; Vermeulen, R. ; van Weeren, R. J. ; Wise, M. W. ; Wucknitz, O. ; Yatawatta, S. ; Zarka, P. ; Zensus, J. A.

published in Astronomy & Astrophysics, 611 (2018)

Abstract: The Sun's activity leads to bursts of radio emission, among other phenomena. An example is type-III radio bursts. They occur frequently and appear as short-lived structures rapidly drifting from high to low frequencies in dynamic radio spectra. They are usually interpreted as signatures of beams of energetic electrons propagating along coronal magnetic field lines. Here we present novel interferometric LOFAR (LOw Frequency ARray) observations of three solar type-III radio bursts and their reverse bursts with high spectral, spatial, and temporal resolution. They are consistent with a propagation of the radio sources along the coronal magnetic field lines with nonuniform speed. Hence, the type-III radio bursts cannot be generated by a monoenergetic electron beam, but by an ensemble of energetic electrons with a spread distribution in velocity and energy. Additionally, the density profile along the propagation path is derived in the corona. It agrees well with three-fold coronal density model by (1961, ApJ, 133, 983).

DOI: 10.1051/0004-6361/201629017

The record appears in these collections:
Royal Observatory of Belgium > Solar Physics & Space Weather (SIDC)
Science Articles > Peer Reviewed Articles
Solar-Terrestrial Centre of Excellence

 Record created 2019-02-04, last modified 2019-02-04