PSR J1847-0130: A Radio Pulsar with Magnetar Spin Characteristics

We report the discovery of PSR J1847-0130, a radio pulsar with a 6.7 s spin period, in the Parkes Multibeam Pulsar Survey of the Galactic plane. The slowdown rate for the pulsar, 1.3 × 10 -12 s s -1 , is high and implies a surface dipole magnetic field strength of 9.4 × 10 13 G. This inferred dipolar magnetic field strength is the highest by far among all known radio pulsars and over twice the "quantum critical field" above which some models predict radio emission should not occur. The inferred dipolar magnetic field strength and period of this pulsar are in the same range as those of the anomalous X-ray pulsars, which have been identified as being "magnetars" whose luminous X-ray emission is powered by their large magnetic fields. We have examined archival ASCA data and place an upper limit on the X-ray luminosity of J1847-0130 that is lower than the luminosities of all but one anomalous X-ray pulsar. The properties of this pulsar prove that inferred dipolar magnetic field strength and period cannot alone be responsible for the unusual high-energy properties of the magnetars and create new challenges for understanding the possible relationship between these two manifestations of young neutron stars.