We report high resolution observations from the Solar Dynamics Observatory/Atmospheric Imaging Assembly ( AIA ) of intensity oscillations in a hot , T \sim 8-10 MK , loop .
The AIA images show a large coronal loop that was rapidly heated following plasma ejection from one of the loop ’ s footpoints .
A wave-like intensity enhancement , seen very clearly in the 131 and 94 Å channel images , propagated ahead of the ejecta along the loop , and was reflected at the opposite footpoint .
The wave reflected four times before fading .
It was only seen in the hot , 131 and 94 Å channels .
The characteristic period and the decay time of the oscillation was \sim 630 and \sim 440 s , respectively .
The phase speed was about 460–510 km s ^ { -1 } which roughly matches the sound speed of the loop ( 430-480 km s ^ { -1 } ) .
The observed properties of the oscillation are consistent with the observations of Doppler shift oscillations discovered by the Solar and Heliospheric Observatory/Solar Ultraviolet Measurement of Emitted Radiation ( SUMER ) and with their interpretation as slow magnetoacoustic waves .
We suggest that the impulsive injection of plasma , following reconnection at one of the loop footpoints , led to rapid heating and the propagation of a longitudinal compressive wave along the loop .
The wave bounces back and forth a couple of times before fading .