soft gamma repeater

A soft gamma repeater (SGR) is probably a magnetar (a highly-magnetic neutron star) that emits bursts of soft (low-energy) gamma rays, each typically lasting less than a second, at irregular intervals. The bursts may be caused by starquakes on the surface crust of the neutron star. SGR bursts, discovered in 1979, are different from gamma-ray bursts, which are one-time events.