Discovery of Two High Magnetic Field Radio Pulsars

Abstract

We report the discovery of two youngisolated radio pulsars with very high inferred magnetic fields. PSRJ1119-6127 has period P=0.407 s, and the largest period derivativeknown among radio pulsars, P=4.0�10 -12. Under standardassumptions these parameters imply a characteristic spin-down age of onlytau c =1.6 kyr and a surface dipole magnetic field strength ofB=4.1�10 13 G. We have measured a stationary period secondderivative for this pulsar, resulting in a braking index of n=2.91+/-0.05.We have also observed a glitch in the rotation of the pulsar, withfractional period change DeltaP/P=-4.4�10 -9. Archival radioimaging data suggest the presence of a previously uncataloged supernovaremnant centered on the pulsar. The second pulsar, PSR J1814-1744,has P=3.975 s and P=7.4�10 -13. These parameters implytau c =85 kyr, and B=5.5�10 13 G, the largest ofany known radio pulsar. Both PSR J1119-6127 and PSR J1814-1744 showapparently normal radio emission in a regime of magnetic field strengthwhere some models predict that no emission should occur. Also, PSRJ1814-1744 has spin parameters similar to the anomalous X-ray pulsar (AXP)1E 2259+586, but shows no discernible X-ray emission. If AXPs areisolated, high magnetic field neutron stars (``magnetars''), theseresults suggest that their unusual attributes are unlikely to bemerely a consequence of their very high inferred magnetic fields.