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PSR J1846-0258 is an object which straddles the boundary between magnetars and rotation powered pulsars. Though behaving for many years as a rotation-powered pulsar, in 2006, it exhibited distinctly magnetar-like behavior - emitting several short har d X-ray bursts, and a flux increase. Here we report on 7 years of post-outburst timing observations of PSR J1846-0258 using the Rossi X-ray Timing Explorer and the Swift X-ray Telescope. We measure the braking index over the post-magnetar outburst period to be $n=2.19pm0.03$. This represents a change of $Delta n=-0.46pm0.03$ or a 14.5$;sigma$ difference from the pre-outburst braking index of $n=2.65pm0.01$, which itself was measured over a span of 6.5 yr. So large and long-lived a change to a pulsar braking index is unprecedented and poses a significant challenge to models of pulsar spin-down.
We report on two years of flux and spin evolution monitoring of 1E 1048.1$-$5937, a 6.5-s X-ray pulsar identified as a magnetar. Using {it Swift} XRT data, we observed an X-ray outburst consisting of an increase in the persistent 1--10 keV flux by a factor of 6.3$pm$0.2, beginning on 2011 December 31 (MJD 55926). Following a delay of $sim100$ days, the magnetar entered a period of large torque variability, with $dot{ u}$ reaching a factor of $4.55pm0.05$ times the nominal value, before decaying in an oscillatory manner over a time scale of months. We show by comparing to previous outbursts from the source that this pattern of behavior may repeat itself with a quasi-period of $sim1800$ days. We compare this phenomenology to periodic torque variations in radio pulsars, finding some similarities which suggest a magnetospheric origin for the behavior of 1E 1048.1$-$5937.
We present the X-ray timing and spectral evolution of the Galactic Center magnetar SGR J1745-2900 for the first ~4 months post-discovery using data obtained with the Nuclear Spectroscopic Telescope Array (NuSTAR)} and Swift observatories. Our timing analysis reveals a large increase in the magnetar spin-down rate by a factor of 2.60 +/- 0.07 over our data span. We further show that the change in spin evolution was likely coincident with a bright X-ray burst observed in 2013 June by Swift, and if so, there was no accompanying discontinuity in the frequency. We find that the source 3-10 keV flux has declined monotonically by a factor of ~2 over an 80-day period post-outburst accompanied by a ~20% decrease in the sources blackbody temperature, although there is evidence for both flux and kT having levelled off. We argue that the torque variations are likely to be magnetospheric in nature and will dominate over any dynamical signatures of orbital motion around Sgr A*.
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