Electromagnetic pulse
From Memory Alpha, the free Star Trek reference.
An electromagnetic pulse (shortened to EM pulse) is a natural or artificial burst of electromagnetic energy.
The electromagnetic pulse from the explosion of the Bynar systems' star going supernova in 2364 knocked out the main computer on Bynaus. (TNG: "11001001")
During Operation Return, the Dominion jammed the Federation's communications by generating a rotating EM pulse. (DS9: "Sacrifice of Angels")
The detection grid of the Imperial Hall on Ilari is vulnerable to a narrow-band EM pulse during its maintenance cycle every ten hours. The USS Voyager considered using this weakness to storm the Hall and remove Tieran from Kes' body in 2373, but Tieran was already aware of the vulnerability and informed them that his soldiers would be waiting. (VOY: "Warlord")
While proposing to destroy the Monac shipyards, Miles O'Brien suggested that the could IKS Rotarran fire an EM pulse at the Monac star to trigger a solar plasma ejection. (DS9: "Shadows and Symbols")
In 2375, B'Elanna Torres attempted to disable a Druoda series 5 long-range tactical armor unit by sending an EM pulse through its power matrix, to no effect. (VOY: "Warhead")
