On-going Monitoring of the LMC Pulsar B0540-69
Abstract
PSR B0540-69 is a remarkable pulsar located in the nearby galaxy the Large Magellanic Cloud. This young, rotation-powered pulsar is by far the most luminous gamma-ray pulsar known with a luminosity 20 times that of the Crab Pulsar. In December, 2011, B0540-69 transitioned to a previously unseen spin-down state with a 36% increase in the spin-down rate. Subsequent observations with the Swift/XRT instrument covering 16 months in 2015 and 2016 found an extremely low braking index of 0.031 +/- 0.013. The on-going Swift monitoring campaign now has an additional 12 months of a phase-connected ephemeris. We find that the braking index remains near 0.0 while the pulsar remains in its high spin-down state. We discuss possible interpretations of this highly unusual spin-down state.
- Publication:
-
American Astronomical Society Meeting Abstracts #231
- Pub Date:
- January 2018
- Bibcode:
- 2018AAS...23124305M