8-12 juin, 2014


The puzzle of low magnetic field magnetars

Paul Scholz (McGill University)

Victoria Kaspi, McGill University Andrew Cumming, McGill University

Magnetars are a class of pulsar that exhibit extremely energetic outbursts and their spin-down energy loss rate is larger than can be explained from rotation alone. These unusual properties are thought to be caused by their enormous magnetic fields (>~ 10^14G). Recently several magnetars have been discovered with spin-down inferred magnetic fields in the range 10^12-10^13G, lower than what was thought necessary to power magnetar outbursts and activity. We report on the discovery and long-term monitoring using the Swift, RXTE, and Chandra X-ray telescopes of low magnetic field magnetar Swift J1822.3-1606. We measure a long-term spin-down rate which implies a dipolar magnetic field that is lower than all previous estimates for this source. We compare Swift J1822.3-1606 to other low magnetic field magnetars and discuss how their existence can be reconciled with the magnetar model.
(doit être confirmé par le SOC)