High-cadence Halpha blue wing observations of a C9.6 solar flare obtained at Big Bear Solar Observatory using the Rapid Dual Imager are presented. Wavelet and time-distance methods were used to study oscillatory power along the ribbon, finding periods of 40 - 80 s during the impulsive phase of the flare. A parametric study found statistically significant intensity oscillations with amplitudes of 3% of the peak flare amplitude, periods of 69 s (14.5 mHz) and oscillation decay times of 500 s. These measured properties are consistent with the existence of flare-induced acoustic waves within the overlying loops.
|Number of pages||6|
|Publication status||Published - 2005|
Keenan, F., Bloomfield, S., Mathioudakis, M., McAteer, R. T. J., Katsiyannis, A., Gallagher, P. T., Brown, D. S., Moore, R., & Williams, D. R. (2005). Observations of H alpha intensity oscillations in a flare ribbon. Astrophysical Journal, 620, 1101-1106.