  High time resolution observations of a white--light flare on the active star
EQ PegB show evidence of intensity variations with a period of approximately 10
s. The period drifts to longer values during the decay phase of the flare. If
the oscillation is interpreted as an impulsively--excited, standing--acoustic
wave in a flare loop, the period implies a loop length of 1.7 Mm and 3.4 Mm for
the case of the fundamental mode and the second harmonic, respectively.
However, the small loop lengths imply a very high modulation depth making the
acoustic interpretation unlikely. A more realistic interpretation may be that
of a fast--MHD wave, with the modulation of the emission being due to the
magnetic field. Alternatively, the variations could be due to a series of
reconnection events. The periodic signature may then arise as a result of the
lateral separation of individual flare loops or current sheets with oscillatory
dynamics (i.e. periodic reconnection).
