The strongest cosmic magnets: Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars

Abstract

Two classes of X-ray pulsars, the Anomalous X-ray Pulsars and the Soft Gamma-ray Repeaters, have been recognized in the last decade as the most promising candidates for being magnetars: isolated neutron stars powered by magnetic energy. I review the observational properties of these objects, focussing on the most recent results, and their interpretation in the magnetar model. Alternative explanations, in particular those based on accretion from residual disks, are also considered. The possible relations between these sources and other classes of neutron stars and astrophysical objects are also discussed.

Submitted to Astromomy and Astrophysics Review (57 pages, 19 figures, 6 tables)

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• The infrared counterpart to the magnetar 1RXS J170849.0-400910
• What do exotic equations of state have to offer?
• A search for the optical counterpart to the magnetar CXOU J010043.1-721134

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