Anomalous X-ray pulsar

Anomalous X-ray Pulsars (AXPs) are now widely believed to be magnetars—young, isolated, highly magnetized neutron stars. These energetic X-ray pulsars are characterized by slow rotation periods of ~2–12 seconds and large magnetic fields of ~10¹³–10¹⁵gauss (1 to 100 gigateslas). There are currently (as of 2009^[update]) 9 known and 1 candidate AXPs. The identification of AXPs with magnetars was motivated by their similarity to another enigmatic class of sources, the soft gamma repeaters.

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