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arXiv · 1611.09782

Swift observations of two outbursts from the magnetar 4U 0142+61

R. F. Archibald·V. M. Kaspi·P. Scholz·A. P. Beardmore·N. Gehrels·J. A. Kennea
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Abstract

4U 0142+61 is one of a small class of persistently bright magnetars. Here we report on a monitoring campaign of 4U 0142+61 from 2011 July 26 - 2016 June 12 using the Swift X-ray Telescope, continuing a 16 year timing campaign with the Rossi X-ray Timing Explorer. We show that 4U 0142+61 had two radiatively loud timing events, on 2011 July 29 and 2015 February 28, both with short soft gamma-ray bursts, and a long-lived flux decay associated with each case. We show that the 2015 timing event resulted in a net spin-down of the pulsar due to over-recovery of a glitch. We compare this timing event to previous such events in other high-magnetic-field pulsars, and discuss net spin-down glitches now seen in several young, high-B pulsars.

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R. F. Archibald, V. M. Kaspi, P. Scholz, A. P. Beardmore, N. Gehrels, J. A. Kennea. 2016-11-29. Swift observations of two outbursts from the magnetar 4U 0142+61. https://doi.org/10.3847/1538-4357%2F834%2F2%2F163

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