Discovery of Two High Magnetic Field Radio Pulsars

Abstract

We report the discovery of two young isolated radio pulsars with very high inferred magnetic fields. PSR J1119−6127 has period P = 0.407 s, and the largest period derivative known among radio pulsars,Ṗ = 4.0×10 −12 . Under standard assumptions these parameters imply a characteristic spin-down age of only τ c = 1.6 kyr and a surface dipole magnetic field strength of B = 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, with fractional period change ∆P/P = −4.4 × 10 −9 . Archival radio imaging data suggest the presence of a previously uncataloged supernova remnant centered on the pulsar. The second pulsar, PSR J1814−1744, has P = 3.975 s andṖ = 7.4 × 10 −13 . These parameters imply τ c = 85 kyr, and B = 5.5 × 10 13 G, the largest of any known radio pulsar.Both PSR J1119−6127 and PSR J1814−1744 show apparently normal radio emission in a regime of magnetic field strength where some models predict that no emission should occur. Also, PSR J1814−1744 has spin parameters similar to the anomalous X-ray pulsar (AXP) 1E 2259+586, but shows no discernible X-ray emission. If AXPs are isolated, high magnetic field neutron stars ("magnetars"), these results suggest that their unusual attributes are unlikely to be merely a consequence of their very high inferred magnetic fields.

The strongest cosmic magnets: soft gamma-ray repeaters and anomalous X-ray pulsars

“…The timing noise is larger in the SGRs. The presence of large variations in the spin-down rate occurring on short timescales has also been confirmed by accurate timing of the radio pulses in XTE J1810−197 [20]. In addition to these gradual changes also glitches have been observed in several magnetars (section 4.2).…”

The magnificent seven: magnetic fields and surface temperature distributions

“…and long periods (Camilo et al 2000;Morris et al 2002;McLaughlin et al 2003) shows that radio emission can still occur at inferred field strengths close to the "quantum critical field" B cr = m 2 e c 3 /eh ≃ 4.4×10 13 G. Therefore it remains unclear if the M7 exhibit no radio emission at all or if we do not detect them because their radio beam is very narrow due to their large light cylinder radius and therefore does not cross the Earth.…”

VLT/NACOobservations of the high-magnetic field radio pulsar PSR J1119-6127

“…Camilo et al (2000) reported d = 2.4−8 kpc, while Gonzalez & Safi-Harb (2003), based on the measured extinction per unit distance in the pulsar direction, estimated d = 5.4−12.6 kpc. Most likely, the pulsar is not further than 8 kpc, according to its location with respect the Carina spiral arm (Camilo et al 2000). In the following we report our results as a function of D 6 = d/(6 kpc).…”