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Sunquakes, first predicted in 1972 by Wolff, are often 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 acoustic waves.  In the years after the first reported observation (by Kosovichev and Zharkova in 1998) only a limited number of flares were seen to be acoustically active.  Early surveys on solar cycle 23, using acoustic holography and construction of time-distance diagrams as main means of detection, show that less than half of flares with data coverage from MDI/SOHO are seismically active, with no clear dependence on time in cycle (Donea 2011).  More recently, with the continuous view of the Sun at high spatial resolution given by SDO, and improved techniques for reliable detection, an increasing number of seismic events have been detected.

In this work, we investigate statistical properties of acoustic egression measurements in the quiet Sun and non-flaring active region to establish significance of acoustic emissions associated with flares. We determine properties of the quiet Sun acoustic sources and derive necessary conditions for detecting flare associated emission based on local helioseismology and photospheric measurements only. We then apply our criteria to analyse X-class flares of the latest Solar Cycle.