Data Centre for Astrophysics
Astronomy Department of the University of Geneva

Extraordinary jet shot by a runaway pulsar


Jets from rotation-powered pulsars so far have only been observed in systems moving subsonically through their ambient medium and/or embedded in their progenitor supernova remnant (SNR). Supersonic runaway pulsars are also expected to produce jets (in addition to their elongated wind nebulae), but they have not been confirmed so far.

We investigated the nature of the jet-like structure associated with the INTEGRAL source IGR J11014-6103 (the “Lighthouse nebula”). The source is a neutron star escaping its parent SNR MSH 11-61A supersonically at a velocity exceeding 1000 km/s. We observed the Lighthouse nebula and its jet-like X-ray structure through dedicated high spatial resolution observations in X-rays (with Chandra) and in the radio band (with ATCA) to derive its morpholgical and spectral properties, and used a precession model to constrain the jet dynamics.

The analysis of our Chandra and ATCA observations have revealed extreme properties of the Lighthouse nebula. We confirm its association with SNR MSH 11-61A through the X-ray/radio spectral and morphological properties of its elongated pulsar wind nebula. Moreover, our results show that the feature is a true pulsar’s jet. It extends highly collimated over ~15pc, displays a clear precession-like modulation, and propagates nearly perpendicular to the system direction of motion, implying that the neutron star’s spin axis in IGR J11014-6103 is almost perpendicular to the direction of the kick received during the supernova explosion.

Our findings confirm that supersonic runaway pulsars are able to produce large-scale jets. In addition they demonstrate that supernovae can impart high kick velocities to misaligned spinning neutron stars, possibly through distinct, exotic, core-collapse mechanisms.

See also the related APOD of 2014-02-21.
DOI: 10.1051/0004-6361/201322588