A Magnetar-like Outburst from a High-B Radio Pulsar
Abstract
Radio pulsars are believed to have their emission powered by the loss of rotational kinetic energy. By contrast, magnetars show intense X-ray and γ-ray radiation whose luminosity greatly exceeds that due to spin down and magnetar luminosity is believed to be powered by intense internal magnetic fields. A basic prediction of this picture is that radio pulsars of high magnetic field should show magnetar-like emission. Here we report on a magnetar-like X-ray outburst from the radio pulsar PSR J1119-6127, heralded by two short bright X-ray bursts on 2016 July 27 and 28. Using target of opportunity data from the Swift X-ray Telescope and NuSTAR, we show that this pulsar’s flux has brightened by a factor of \gt 160 in the 0.5-10 keV band, and that its previously soft X-ray spectrum has undergone a strong hardening with strong pulsations appearing for the first time above 2.5 keV, with phase-averaged emission detectable up to 25 keV. By comparing Swift-XRT and NuSTAR timing data with a pre-outburst ephemeris derived from Fermi Large Area Telescope data, we find that the source has contemporaneously undergone a large spin-up glitch of amplitude {{Δ }}ν /ν =5.74(8)× {10}-6. The collection of phenomena observed thus far in this outburst strongly mirrors those in most magnetar outbursts and provides an unambiguous connection between the radio pulsar and magnetar populations.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2016
- DOI:
- 10.3847/2041-8205/829/1/L21
- arXiv:
- arXiv:1608.01007
- Bibcode:
- 2016ApJ...829L..21A
- Keywords:
-
- pulsars: general;
- pulsars: individual: PSR J1119-6127;
- stars: magnetars;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 7 pages, 3 figures, accepted to ApJL