Sun-quakes were first predicted in 1972 by Wolff and are seen in the Sun’s photosphere as a burst of outwardly emanating ripples, caused by a sudden release of energy below the surface that produces sound waves. In the years after the first reported observation of a sun-quake, by Kosovichev and Zharkov in 1998, only a limited number of flares were seen to be seismically active. More recently, the continuous view of the Sun at high spatial resolution given by SDO, and new techniques for the reliable detection of sun-quakes, has led to an increasing number of observations of seismically active events. However, there are still a number of events where the results of current detection methods are inconclusive.

In this statistical study of acoustically active flares we present the automated code for detection of sun-quakes and evaluate the acoustic emission statistics. Particular attention is paid to properties of flares with lower acoustic emission, seeking to establish a well-defined threshold for detection.