Abstract
We explore the correlations between the inferred reconnection rate and hard X-ray spectral hardness for two double-ribbon flares on 2003 November 1 and 2005 May 17 in this paper. The magnetic reconnection rate of φ rec is derived from the time rate of change of the product between the normal magnetic field and the newly brightened ribbon area of TRACE 1600 Å observations. And the spectral index of γ is derived from RHESSI hard X-ray data. Both events show a soft-hard-soft spectral behaviour in the rise-peak-decay phases. An anti-correlated behaviour is found between the time evolution of reconnection rate and spectral index. From the regression analysis, we obtain a negative power-law dependence and quantify the relationship between these two quantities. This is consistent with the simulation results before, and further confirms the importance of magnetic reconnection for the electron acceleration in solar flares.
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Ning, Z. Magnetic reconnection rate and spectral index for two double-ribbon flares. Astrophys Space Sci 314, 137–143 (2008). https://doi.org/10.1007/s10509-008-9749-z
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DOI: https://doi.org/10.1007/s10509-008-9749-z