Analysis of Intermittency in Submillimeter Radio and Hard X-Ray Data During the Impulsive Phase of a Solar Flare

Data de publicação
Solar Physics
Citações (Scopus)
GimenezdeCastro G.
Simoes P.J.A.
Raulin J.-P.
Guimaraes O.M.
Título da Revista
ISSN da Revista
Título de Volume
Membros da banca
© 2016, Springer Science+Business Media Dordrecht.We present an analysis of intermittent processes occurring during the impulsive phase of the flare SOL2012-03-13, using hard X-rays and submillimeter radio data. Intermittency is a key characteristic in turbulent plasmas and has so far only been analyzed for hard X-ray data. Since in a typical flare the same accelerated electron population is believed to produce both hard X-rays and gyrosynchrotron radiation, we compare the two time profiles by searching for intermittency signatures. For this, we define a cross-wavelet power spectrum, which is used to obtain the local intermittency measure, or LIM. When greater than three, the square LIM coefficients indicate a local intermittent process. The LIM2 coefficient distribution in time and scale helps to identify avalanche or cascade energy release processes. We find two different and well-separated intermittent behaviors in the submillimeter data: for scales greater than 20 s, a broad distribution during the rising and maximum phases of the emission seems to favor a cascade process; for scales below 1 s, short pulses centered on the peak time are representative of avalanches. When applying the same analysis to hard X-rays, we find that only the scales above 10 s produce a distribution related to a cascade energy fragmentation. Our results suggest that different acceleration mechanisms are responsible for tens of keV and MeV energy ranges of electrons.
Assuntos Scopus
DOI (Texto completo)