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Multi-wavelength observations of an unusual impulsive flare associated with CME

Wahab Uddin·Rajmal Jain·Keiji Yoshimura·Ramesh Chandra·T. Sakao·T. Kosugi·Anita Joshi·M. R. Despande
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Abstract

We present the results of a detailed analysis of multi-wavelength observations of a very impulsive solar flare 1B/M6.7, which occurred on 10 March, 2001 in NOAA AR 9368 (N27 W42). The observations show that the flare is very impulsive with very hard spectrum in HXR that reveal non-thermal emission was most dominant. On the other hand this flare also produced type II radio burst and coronal mass ejections (CME), which are not general characteristics for impulsive flares. In H$α$ we observed the bright mass ejecta (BME) followed by drak mass ejecta (DME). Based on the consistence of the onset times and direction of BME and CME, we conclude that these two phenomena are closely associated. It is inferred that the energy build-up took place due to photospheric reconnection between emerging positive parasitic polarity and predominant negative polarity, which resulted as a consequence of flux cancellation. The shear increased to $>80^o$ due to further emergence of positive parasitic polarity causing strongly enhanced cancellation of flux. It appears that such enhanced magnetic flux cancellation in a strongly sheared region triggered the impulsive flare.

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Wahab Uddin, Rajmal Jain, Keiji Yoshimura, Ramesh Chandra, T. Sakao, T. Kosugi, Anita Joshi, M. R. Despande. 2004-10-07. Multi-wavelength observations of an unusual impulsive flare associated with CME. https://doi.org/10.1007/s11207-004-5002-2

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