Anomalous X-ray Pulsars (AXPs) are now widely believed to be magnetars—young, isolated, highly magnetized neutron stars. These energtic X-raypulsars are characterized by slow rotation periods of ~5–12 seconds and large magnetic fields of ~1013–1015gauss. There are currently 6 known and 2 candidate AXPs. The identification of AXPs with magnetars was motivated by their similarity to another enigmatic class of sources, the soft gamma repeaters.
