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arXiv · 0903.2138

Transient Magnetic and Doppler Features Related to the White-light Flares in NOAA 10486

R. A. Maurya·A. Ambastha
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Abstract

Rapidly moving transient features have been detected in magnetic and Doppler images of super-active region NOAA 10486 during the X17/4B flare of 28 October 2003 and the X10/2B flare of 29 October 2003. Both these flares were extremely energetic white-light events. The transient features appeared during impulsive phases of the flares and moved with speeds ranging from 30 to 50 km s$^{-1}$. These features were located near the previously reported compact acoustic \cite{Donea05} and seismic sources \cite{Zharkova07}. We examine the origin of these features and their relationship with various aspects of the flares, {\it viz.}, hard X-ray emission sources and flare kernels observed at different layers - (i) photosphere (white-light continuum), (ii) chromosphere (H$α$ 6563Å), (iii) temperature minimum region (UV 1600Å), and (iv) transition region (UV 284Å).

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R. A. Maurya, A. Ambastha. 2009-06-01. Transient Magnetic and Doppler Features Related to the White-light Flares in NOAA 10486. https://doi.org/10.1007/s11207-009-9397-7

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