Post-outburst timing of the magnetically active pulsar J1846-0258

The similar to 800 yr-old pulsar PSR J1846-0258 in the supernova remnant Kes 75 is a unique transition object between rotation-powered pulsars and magnetars. While it typically behaves as a rotation-powered pulsar, in 2006 it exhibited a distinctly magnetar-like outburst accompanied by a large glitch with an unusual over-recovery. We present X-ray timing observations taken with the Rossi X-ray Timing Explorer after the X-ray outburst and accompanying glitch had recovered. We observe that the braking index of the pulsar, previously measured to be n = 2.65 +/- 0.01 has decreased by 18 +/- 5%. We also note a persistent increase in the timing noise relative to the pre-outburst level, reminiscent of behavior previously observed from some magnetars.