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arXiv · 1007.2829

Post-outburst Observations of the Magnetically Active Pulsar J1846-0258: a new braking index, increased timing noise, and radiative recovery

Margaret A. Livingstone·C. -Y. Ng·Victoria M. Kaspi·Fotis P. Gavriil·E. V. Gotthelf
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Abstract

The ~800 yr-old pulsar J1846-0258 is a unique transition object between rotation-powered pulsars and magnetars: though behaving like a rotation-powered pulsar most of the time, in 2006 it exhibited a distinctly magnetar-like outburst accompanied by a large glitch. Here we present X-ray timing observations taken with the Rossi X-ray Timing Explorer over a 2.2-yr period after the X-ray outburst and glitch had recovered. We observe that the braking index of the pulsar, previously measured to be n=2.65+/-0.01, is now n=2.16+/-0.13, a decrease of 18+/-5%. We also note a persistent increase in the timing noise relative to the pre-outburst level. Despite the timing changes, a 2009 Chandra X-ray Observatory observation shows that the X-ray flux and spectrum of the pulsar and its wind nebula are consistent with the quiescent levels observed in 2000.

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Margaret A. Livingstone, C. -Y. Ng, Victoria M. Kaspi, Fotis P. Gavriil, E. V. Gotthelf. 2011-02-21. Post-outburst Observations of the Magnetically Active Pulsar J1846-0258: a new braking index, increased timing noise, and radiative recovery. https://doi.org/10.1088/0004-637x%2F730%2F2%2F66

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