A Peculiar Microwave Quasi-periodic Pulsation with Zigzag Pattern in a CME-related Flare on 2005-01-15
aa r X i v : . [ a s t r o - ph . S R ] J un Solar and Astrophysical Dynamos and Magnetic ActivityProceedings IAU Symposium No. 294, 2012A.G. Kosovichev, E.M. de Gouveia Dal Pino, & Y.Yan c (cid:13) An Peculiar Microwave Quasi-periodicPulsations with Zigzag Pattern in aCME-related Flare on 2005-01-15
Baolin Tan Key Laboratory of Solar Activity, National Astronomical Observatories of the ChineseAcademy of Sciences, Beijing 100012, China.email: [email protected]
Abstract.
A microwave quasi-periodic pulsation with zigzag pattern (Z-QPP) in a solar flare on 2005-01-15 is observed by the Chinese Solar Broadband Spectrometer in Huairou (SBRS/Huairou)at 1.10-1.34 GHz. The zigzag pulsation occurred just in the early rising phase of the flarewith weakly right-handed circular polarization. Its period is only several decades millisecond.Particularly, before and after the pulsation, there are many spectral fine structures, such as zebrapatterns, fibers, and millisecond spikes. The microwave Z-QPP can provide some kinematicinformation of the source region in the early rising phase of the flare, and the source widthchanges from ∼ Keywords. solar flare, microwave bursts, fine structures
Solar microwave spectral fine structures are the most important and interesting phe-nomena, which can provide many intrinsic features of solar eruptions. This work reportsfirst time a peculiar fine structure: a microwave quasi-periodic pulsation (QPP) withzigzag pattern (abbreviated as Z-QPP, hereafter) in a flare on 2005-01-15.
Figure 1.
Left panels are the profiles of the M8.6 long-duration flare on 2005-1-15. Soft X-rayintensity observed by GOES (upper), microwave emission of left-handed circular polarizationat 1.20 GHz (middle), and the microwave emission of right-handed circular polarization at 1.20GHz (bottom). Right panels are the spectrogram of microwave quasi-periodic pulsation withzigzag pattern (Z-QPP) in the early rising phase of the flare. v ), and the width of source region (L) can be estimated: v = 2 dff dt H n , L = 2 △ ff H n . (0.1) H n is the scale length of plasma density in the background for the source motion andin the source region for the energetic particles.The above estimation of the Z-QPP indicates the source region moves in a speed from275-93 km/s upwards, the source width expands from 1000 km to 3300 km, and theassociated speeds of energetic particles is about 0.13 0.53 c , 0.53-0.8 c , and 0.36-0.9 c inthe three paragraphs, respectively. Here, c is the light speed. Before and after the Z-QPP,there are many spectral fine structures, such as zebra patterns, fibers and millisecondspikes, etc. Some of them are marked in Figure 1. The abundant spectral fine structuresreflect the dynamic features of the non-thermal particles (Huang & Tan, 2012). Acknowledgements
This work is supported by NSFC Grant No. 11273030, 10921303, MOST Grant No.2011CB811401, and the National Major Scientific Equipment R&D Project ZDYZ2009-3.
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