Ion gun

Asgard energy weapons are the primary weapon used by the vessels of the Asgard Fleet. The weapons are significantly superior to Goa'uld weapons, though Anubis was able to upgrade Goa'uld shields, increasing their durability. Energy weapons are particularly effective against Replicator ships which just emerge from hyperspace. While suffering from a string of alternate SG-1s coming through the Stargate, the Asgard scientist Kvasir allowed the SGC to borrow an energy weapon. Normally, however, the Asgard do not allow their weapons to be used by other races, for fear that corrupt members of a race might use it against them.